Specialized Hardrock Disc 2011 or Diamondback Outlook?

Which outlook, as there are many models from different years?

Does it have rear suspension?

In anycase I think better are to be had like the Carrera Vulcan and Decathlon Rockrider series.

You need to try the models out to get the sizing correct. You could be anywhere from an 18inch plus - different brands are measured in different ways and have markedly varying geometry. The Hardrock has quite a long top tube for example. Reach is very important, and seatposts are much easier to adjust.

Some Outlooks had rear sus. The two bikes are very similar, the Hardrock having the better frame. I still think there are better buys for this cash though, both have pretty basic forks and parts and will be best suited to lighter off roading.

Definitely the right thing to try some differnt frames of the same model. 6ft 3 is tall, but not that tall! Depends on many factors.