If you're looking for a pure "mountain bike", take a look at the EG Bali
or EG Barcelona
Both are full-suspension mountain bikes with lots of nice components and features. I personally ride the Barcelona, and it's perfect for me. I enjoy pedaling and only need assistance on big hills or when I'm tired after a long ride. It's 200w motor isn't super powerful, but if you're just looking for assistance, it's a great pedal assist bike. You'll have two power-assist settings -- Economy (E) or Standard (S). In economy you'll feel just a small amount of assistance, but you'll get the most range. In standard, you'll get lots of assistance and it feels like the motor is doing almost all of the work. Even though the bike has a throttle, it's quite unimpressive from a dead stop. But it's a great way to keep your momentum or stop pedalling after you get going.
If you don't want to do any pedalling, this bike is probably not for you. In that case, a kit might be a better choice. They'll take a bit more work, and your other bike will be useless as a "regular bike" after you're done with the conversion. Lots of different kit options...
If you don't have a problem paying $5000+ -- take a look at the Optibike...
Last edited by ecowheelz; 10-19-09 at 08:19 AM.