Depends a lot on how often you intend to train. The harder you train the quicker a cheaper iaito is gonna wear out. Our dojo used to use some of those, and we had difficulty with the handle wraps getting loose after a year or two. Add to that a really awful balance and they just weren't up to snuff. Admittedly that was like 7 years ago. They may very well have changed since then.
We purchase most of our swords from http://www.swordstore.com
and have for years. Nothing but good things to say. I've heard good things about the better swords from Tozando, but the extreme low end doesn't seem to have many fans.
You can also trust http://www.e-bogu.com
by all accounts.
I'd strongly recommend asking your instructor as different styles have different preferences for various things like balance, length, type of tip on the blade, etc.