That's a favorite tank on this forum. =] They're stylish, durable, and they have a good filter (although it needs baffling).
I'd definitely get it. =]
And yeah you could definitely house a snail, some shrimp, and a betta in there. though I gotta say the shrimp might be more comfortable and come out of hiding more if they get their own space. =]
I highly suggest cycling and getting stem plants if the snail you want is a mystery snail. =]
if your snail starts eating your plants then try feeding it blanched cucumber. =] Plus it's cute when they start rolling them around the tank. <3