A lot of people like the 450r rear shock. I did not. It made the bike sit to low. I like the 250R shock. The most common is the 400EX. It is also the most affordable. If you find decent deals you can get banshee fronts, 400EX rear, and KOR bushings for less than 100 bucks. Well worth it IMO. Set the banshee shocks to the softest setting and set up the rear and you will be happy with you $100 investment.