Or the 3 series... Ive rented one of those away (I just realised that they were under $500). They are good bikes. they have mechanical disk brakes, and an aluminium frame, and when I rode it away It seemed very reliable. I was riding on singletrack trails with 4 foot step downs and stuff, and the shocks definately could have been a bit more plush, but then again thats not what they were designed for. The rear derailleur was pretty screwed up, but thats im not sure what caused that, the person who rented it before me did. good luck in your search