I'm relatively new to betta keeping, but I believe most would recommend cycling a 5 gallon tank. If not, other more experienced keepers can give you water change advice.
As for the Hawkeye 5 gallon, I have that tank in my bedroom and it is nice, but I'm getting frustrated with the fact that, at least my tank, seems to hold a lot of condensation in the hood. That condensation then drips down the sides/back of the tank when I open the hood for maintenance. Also, the condensation is up in the light fixture and makes me a bit nervous about possible problems.
My frustration with the water running down the side of the tank is mainly because this tank is sitting on a dresser and I'm thinking it is gonna damage the wood. I've put something under it, but it's frustrating none the less.
If this were sitting on a different surface I wouldn't be quite as annoyed by it.
If you do a search on this forum for Hawkeye you should find input from others with it.
I had to get another 5 gallon yesterday and I ended up going with a standard 5 gallon glass. Its a kit from Petsmart http://www.petsmart.com/product/inde...461&lmdn=Brand
and I plan on swapping out the incandescent bulb with a florescent one so I can have live plants, but that wouldn't be necessary if you had silk/plastic plants.
Just my opinion.