Another newbie full of questions

Hi there everyone. This is my first post and inevitably I have a few questions for you good folks. I’m new to M-4/ AR rifles. I did get a little practice back in the 80’s with the newly minted M16A2 in the Marines. But I never knew half as much about the weapon as you guys seem to have amased here. I’ve devoted several hours to reading old posts, but like everything else new I’m a little bewildered.
I was going to purchase my first m-4 soon and never knew there were so many options. Like many I was all set to grab the first Bushmaster I saw on the shelf until my eyes were opened here. My first question regards New York state laws. I appears I must get a fixed stock, 10 round mag, no bayonet lug rifle with no flash suppressor? How do they define that? What’s the difference between a flash suppressor and a muzzle brake or a compensator? Do these laws really limit me much?
I would like to start out with a better than average weapon. One that I will not have to continually trade up with. Colt seems very hard to find here. I thought S&W would mean quality, but it appears there may be better alternatives available?
Iron sights are what I’m looking for but with a removable handle or picatinny rails to add sights in the future if desired.
Bushmaster seems to be the only one I’ve seen that makes a piston gas system as stock in at least one model. Is it really all that important or will it potentially just mean one more component that can fail and be difficult to replace?
What the heck is staking? It’s talked about quite a bit here, but like much else I’ve not found a definition.
The posts about the ADS seem interesting. Would that be a good overall system or would anyone care to put their two cents in?
Thanks so much all. I know newbie posts can be annoying sometimes, but how else can a guy learn?

Being that you’re in NY State I’d recommend a S&W M&P15FT

As far as staking goes read through these threads.

I see what staking is. After reading it several times I believe I now know what staking does. Will the 1 in 9 twist on the S&W mean slightly lesser accuracy past 100 meters as opposed to 1 in 7? $1,754 retail must mean less at street price, but is the difference in cost worth it over the price I’ve seen in the forum for an ADS? Or can I not have an ADS in NY?

No other opinions? Didn’t mean to overwhelm anybody.

1x9 will suit you fine for bullet weights from 40-69gr. Sometimes 1x9 will stabilize even longer heavier bullets up to 77gr but not often.

If all you’ll like shoot is 50-69gr 1x9 will be great. Most people only shoot 55gr due to the high cost of ammo.