Hey... now that I know you're in Chicagoland, I can offer some better advice.
Metra allows full-sized bikes on their trains so don't be too concerned with getting a folder. Another thing... because they allow full-sized bikes, you don't necessarily need to fold your bike when you get on the train. If you do get a folder, don't worry about size (unless you plan on using it on the "L" during rush hour).
My only concern with the Kent Ultralite is that it might be too small for you. Definitely test ride it before you buy.
--sam