Long Island here , I just picked up a CETME G-3 from these guys and the gun works like a dream , I do however understand why some people dont like them . They are basically known for having alot of the things most gunstores in Long Island / NYC dont have , including alot of surplus stuff.
Coliseum guns have a lot of really good guns including alot of Kimbers , Berettas and most anything else , but they are also lacking in the manners dept. as well as some of their guys dont know shit.They are also pricey.
TNT in Seaford has good selection and the prices are ok but many of the kids that work there dont know much, but really believe they do and really sell people alot of BS.
American Outdoor sports has a decent selection of long arms but not to many handguns , they are a little pricey as well and customer service is spotty.They do carry alot of outdoors and camping equipt.
TNT in floral park is small with limited stock.
I wont deal with Guns and Ammo at all the guy is a jerk.
The best place to go for handguns is New York Ironworks in the city , they have good prices on LE guns and a very good selection of guns and LE gear. You can also find alot of high end / hard to find optics and guns there.