Pros: I have a 2010 d660 and it is a awsome 29er i love

Cons: the 1x9 i needed the granny gesr canged to 3x9 and now its the only bike i want to ride

Recommendation: great bike and at a good price now they have the d680 that bike is sweet for 2011

Pros: i am 295 lbs 6ft 6 this bike handels and climbs like a beast reba shox awsome. 21 inch frame.

Cons: 9speed sometimes you wish you had a little more

Recommendation: if your big and want a badass bike this is the one for you. it will also give you a work out.

Pros: Super light weight; comfortable geometry, especially for taller riders; seemed to float over obstacles and rides like a cross between a hardtail and full suspension rig.

Cons: Standard build is 1x9 which may not be for everyone.

Recommendation: Redline has really made a commitment to building great 29er bikes and in the d660 it shows. Simple, solid build that's lightweight and affordable. If you're looking for a hardtail 29er this is a great choice.