So the 7614 Ikon shocks at New Bonneville are $100 more than the standard Ikon shocks (7610?), and for that extra $100 they have threaded preload adjustment and are made of aluminum. I don't give a damn about weight on my bike, and I am a little concerned about aluminum being less durable than steel, which is a point in favor of the cheaper ones; but what about the preload adjustment? Infinite preload adjustment is nice. Which should I go with? Opinions?