Looking to get a new casting reel for frogs, poppers, and buzzbaits on 40lb braid. Considering Shimano Curado K, Casitas, Abu Garcia Revo X Gen4 or Daiwa Tatula CT in a 7speed. Does anyone have suggestions on these reels? 

Any of those reels will work just fine. Whichever one feels best in your hand is the right one.

 

I just finished building a froggin flippin combo.. uses a fuego ct with 65lb braid.i almost went with a tatula SV for flipping and because frogs fly so poorly though the air, but I've been very happy with the fuego. It helps that the fuego is so inexpensive. Keep in mind frogs take quite a bit of brakes!

The K would top my list

Another vote for K here also.  Just picked up my second one (both are 8.5:1) and love those reels.

Buzz baits are not very aerodynamic and not the best casting lures. To give you versatility and ease of control when you need it I’d suggest the Tatula SV or find a good deal on a Zillion SV. 

Whichever fits in your hand the best. But if you are considering a Curado K or Tatula why not Revos SX? The SX would be my pick then Tatula then K. I absolutely love the Gen 4 SX.