Would like to know a little bit about cavalry lowers from folks that have used them. I have a super lightweight upper with regular lower ,but would like to go lighter. How is the durability, can you use an after market trigger, pros cons ect.? It will be used as a fun gun (blaster) not a bet my life on it weapon.
Thanks 
I have owned several Cav Arms lowers, both in full-auto (post samples) and semi-auto. I think they are great receivers and are a very good deal but I would not recommend one if you do not already have a regular AR or two.
As far as I know you can run an after market drop-in trigger in them but there may be some fitting required depending on the size of trigger components. If I were going to put a drop-in trigger in a Cav Arms lower I would not worry too much but make sure you have a Dremel or file handy just in case.
Pros:
-Lightweight
-Come in different colors (used to be a lot more colors)
-Cut to accept grease gun mags
-Very durable
-Very forgiving of pistol calibers (the flexing receiver reduces trigger slap on non ramped 9mm bolts)
Cons:
-Non standard pins
-Fixed length stock (A1 with spacers)
-Carbine buffer in a rifle stock
-Non standard external shape
-Random fitment issues