Giant and Kona would be the two companies I would suggest. Personaly I perfer Kona since I have ridden there bikes since they first came out and have never had a problem with them. Their Out of Bounds series are great all around bikes. They are able to handle the sickest drops and you can stin be comfortable on them when doing 4+ hour rides. The Giant are great also. They are abit easier to ride up hills because they don't bob as much do to their susspension.