I hands down no questions asked am a HUGE fan of my new aqueon evolve 4 tanks...Ive only had them up and running for 1 full day now but im hooked. Deffinitely has too much flow tho! you have to baffle it with a sponge...dont use a heavy duty sponge it will blow the motor...I buy a peice of sponge at the petstore, they sell peices of sponge in the filter section. Use siscors to make a little hole and slip the sponge over like a sock or tie it on with an elastic...make sense? Just make sure the sponge has big porus holes like I said before it will blow the motor of the sponge is too thick, I use a thin peice of sponge and I kind of pull on to spread the porus holes out. Asside from the flow I LOVE the lighting, the look and the size. The evolve 8 is bigger but Id rather do water changes in the small tanks, just easier, but if you just have 1 betta at work you could go with the 8. I have 4 bettas so I like smaller tanks.
This is the tank...kind of pricey but in my opinion worth the money!
I dont recommend the evolve 2 though, these tanks run small...the 4 is a 3.2 gal, the 8 is more like a 6 gal so I couldnt imagine what the 2 is, maybe a 1 gal? Good luck with your choice!