I'm a mechanic at a bike shop and I have worked on these bicycle shaped objects called "Landrider" In my humble opinion you would be much better served by going to (sigh I can't believe I'm saying this) Wal-mart and buying a three speed Huffy. The derailieur system on the Landrider is driven by a rubber band connecting from a pulley on the back of the deraillieur to a modified spoke protector. If the band breaks you're screwed. Also if you have to stop suddenly be prepared for your drivetrain to crunch and grind like a 15 yr old trying to drive stick for the first time. Do yourself a favor go to a bike shop (one where they don't sell video games a few aisles over) and browse their selections.
Bottom line if you're going to spend that kind of money get something worthwhile.