The link won't come up for me, but I googled it! It sounds like a very nice aquarium. Six gallons is nicely roomy for a single betta. I personally don't like round aquariums, since there is so much diffraction it can be hard to actually see your fish half the time.
Biggest things to watch out for would be the filter intake and output - those might need to be shielded/baffled to keep your bettas fins from being damaged on the one side, and to keep it from making to much current/water movement on the outflow.
Is there a place for a heater cord to go in? I'd check for that.
And of course, if you get it, you are pretty much required to post pictures once it's set up so we can see it!