What do you like? For what application? different hat for range, out & about, fishing, golfing, work, etc. or all the same hat? Specific issues you face? giant head? tiny cranium?
Let’s hear what you use and what you like, what you’ve used that didn’t work out for you, what your criteria is for selection, and lets see some pics of hats in action.
ball cap. but it has to form my head. HSGI did a really good job with their hieght sizing in their flexfit prototypes. My auburn football ball cap is like that to. I like the top of my hat to touch the top of my head, not be 1-3" off like most hats.
I rock the ball cap at the range, in the yard working, or at night when i don’t have sun glasses on. I’ve found very few hats that work with sunglasses. they always have a tendency to either push them odwn into your nose to where it hurts, or the ear pieces are so long that the hat pushes the glasses foward.
While the idea of built in hearing protection was a great thought at first, it’s not really a necessity for me. plus i prefer my surefire plugs over anything else.
I like a thin ball cap just like the ones BCM gives away. 
I primarily use a hat to help me stay cool in the sun, and to keep the sun out of my eyes.
Boonie hats are prime for any outdoor activity. Hiking (the best for this), shooting, fishing, biking, etc. The brim all the way around keeps sun off the back of my neck, ears, and more of my face. I thank myself when I get home after a day of activity.
I have quite a few of these. Some are hiking brands (Marmot, OR), some are tactical ones (SKD). All of them are used.
Ball caps are a distant second for me, as they offer no protection for the sides of your face, or your ears, or the rear of your neck.
That being said, I do like a nice fitted ball cap for kicking around town. Ball caps are much more “greyman” and they blend in for day to day use since just about everybody wears them.
The Larue hats are my fave of this category. Good colors, simple, soft and comfortable.
Hats are to prevent sunburn, keep sweat out of my eyes, brass out of my eyepro.
No preference for adjustable or flex fit. Fitted is optimal if it’s sized right, but they can wear loose. I like a comfortable fit at the top with a little extra material (not loose or baggy though). No button. It should sit just below the tips of my ears. Snug fit around my head, but not tight.
My hat size: 7 1/2 LO.
My favorite hat for fit right now is my nineteen47.com Minnesota Twins hat, size XL. I also like the way the BCM hat fits, the one with the flag on the front.
No trucker hats. Not ever.
I still have an old BHI subdued flag hat that goes with me everywhere - makes sense whenever I’m too ashamed of wearing an airsoft shop hat.
I’ll wear a HSGI hat when I go shooting or on practice marches to provide shade for my face:
It’s extremely comfortable, and I have a shortened name tape that I stick on the back.
A boonie hat sounds like a great idea for providing shade for the back of my neck, though.
Sports - wide absorbent headbands; I wear glasses and need to prevent sweat to run on the lenses.
Hiking - boonie hat for all-around sun protection; sometimes I wear ballcaps.
Firearms training - modified ballcaps. I trim the brim short. I like wearing the cap low and have found standard brim to come into my visual field more than I’d like.
I favorite all around cap is the HSGI, I have like 20… YAMMI’s/Short Brims/Standards…
I have a 7-3/4" Dome and wear the standard cap when my hair is short…
If I grow out my hair I wear my Surefire Cap…
Fishing I wear a vented full brim…
HSGI Khaki with NO VELCRO
Standard HSGI Multicam
Tactical Hard Hat…
HSGI Boonie
Fishing Hat… Buddy Wearing my Surfire Cap…
Surefire Cap with Hippie Hair
This is the Hat I wear 90% of the Time… HSGI Multicam
Custom Jihad…
CXS
Mine is my motivation.
Every time I hit the range I see it, and the hate train leaves the station.
PJ
Pretty much what’s already been stated here; MC boonie for hiking and hunting, very light weight ball cap for running, BCM or VTAC caps for everyday wear and the free ball caps that LA Police Gear sent me for range time.
Pat
My preferred hat is the Boonie style. I have them in many colors depending on the the temp and the occasion. I like them because they offer full sun protection and I can just fold them up and put them in my pocket when needed.
First, I find this a little unsettling because, frankly, don’t you have to wear a yellow visor? 
I tend to avoid the overly ‘i like shooting or army stuff’ hats. I presently use a few:
[ul]
[li]Lightweight Mountain Hardwear nylon (almost shot)[/li][li]Generic “close to marpat brown” adjustable organic cotton cap (5 bucks @ walmart). Currently the first one I grab.[/li][li]Proper Cotton/Poly patrol cap in khaki (RIT to ‘darker’ brown)[/li][li]Outdoor Research Radar cap (new, i like this one. It will probably replace patrol cap above)[/li][li]Proper Boonie in khaki for sunny or rainy days (would like to replace this with an OR Helios/Sombrero). I like the versatility and full coverage. [/li][/ul]
the 215gear blended hat has become my fave for hot weather - the mesh panels in the back provide more ventilation than a solid fabric hat.
When I’m hunting I wear a boonie hat. The round brim allows me to slowly move and look around without making the movement so noticeable. A ball cap would exaggerate the movement because of the bill. Everything else I wear a ball cap. Being bald on top I have to wear a cap of some type in the sun. Sun burnt head really hurts.
That is my favorite ball cap. I use it to keep rain and sun off of my “solar panel for a sex machine” bald head. My favortire winter cap is the Larue Tactical ball cap it is much thicker and keeps the chrome dome warm. When it is really cold I wear a night watchmans cap, while hunting a boonie(jungle) hat, and when at theme parks, shopping outside, at zoo with the fam etc. I wear a Tilley LTM5 Airflo.
Nikes Dri fit feather caps are pretty much what I stick with during the warmer months. The can be had for $20 or probably cheaper depending on where you look and have easily done the best job at repelling moisture to keep my dome cool as well as offering protection from the sun. The material is slightly elastic so it offers the perfect fit for just about any sized head. Another point to mention is that it weighs virtually nothing in comparison to most of the hats Ive worn or handled.
If it’s not a MICH helmet or a beanie, pretty much exclusively baseball caps. I have a bunch, but I’ve got a small, misshapen bald dome (I’m so ugly that my hair ran away from my face) and most just don’t fit well enough for me to want to wear.
One of the few exceptions is my Lightfighter hat. I have no idea who the manufacturer is. It fits right, is light enough to not hold in to much heat and thick enough to absorb most sweat.
2nd Place is a lightweight hat from Kuhl: https://www.kuhl.com/products/Strand-Hat.html …though mine’s khaki. I get the feeling they don’t offer it any more.
3rd place is one I wear only in the winter, because it’s pretty heavy. A black twill baseball cap with the Enron logo on the front. Some folks object to the logo, but they can kiss my ass, they’re history and it’s a nice hat.
I pretty much wear whatever. If it is really hot outside with a good amount of humidity, I definitely wear the 215 Gear Mesh hat. Other than that, I just grab which ever one it is. Got a mix if everything. And I’m pretty sure the only one I bought is the Outdoor Research Goretex hat
Often, yes. But there are times when it’s best not to.