Welcome to Long Island! It's an amazing place to fly out of-- such great views!
I've flown out of KISP and KHWV with both Heritage flight academy and mid-island. Heritage is out of KISP and mid island, while having an islip locale, I currently fly with them out of KHWV. Honestly, heritage is amazing for training and I'd go back there to get training but they are terrible for building time with or taking pleasure trips with. They only let me rent the 172's for 4 hour chunks of time because they are extremely busy all the time. That just did not work for me and I had to switch. They did have a pretty solid 152 that was cheap( 125 and hour) that you could take for as long as you wanted, but it was so slow that it took forever to get anywhere!
Mid Island out at KHWV is a great, small, easy place. They let you schedule online as far in advance as you want and you can take the plane as far as you want and for as long as you want. They have a huge fleet, 4 172's about 6 or so 152's, 2 warriors, an archer and some
Small LSA planes. The 172's are no frills, just standard VFR planes with no gps but they fly great. I've literally never not gotten a plane for the time and day I wanted. They offer a discount of 20% if you fly early on Saturday or Sunday( plane must be back by 1000am.) and offer pilot clubs which you can pay a small upfront fee and that reduces the hourly fee even more. 2 weeks ago I got 1.7 hours in a 172 for 186 bucks taking advantage of their pilot clubs and early bird discount. Honestly, around here, that's incredibly good! I'd totally recommend them.