depends on how far you want to go with power increases.....the QSC and STM Rage 3 are about equal as far as performance, tun-ability and strength and are a great upgrade over the OEM primary on stock or lightly modified engines. If you intend on running big mud tires, then a lot of people like the Rage 6 as it applies more clamping force on the belt and prevents it from slipping....if you intend on adding a turbo or other major upgrades, then you should consider the Rage 8.....it is all about how much you can afford to spend!
Don't know anything about tuning or anything about a STM. I got a qsc from Kris and called him when I changed tires. He told me what weights to put where and it was easy to do myself. Like Heavy said, It's all about what you are gonna do with it. Either way you go, it is a noticable difference compared to stock.
I'm always a phone call away! I'm doing this full time now so reaching me should never be an issue. As everyone here has stated making the physical adjustments on the clutches is easy. In my personal opinion pick a vendor that will support you not only during the "sale" but after. If you want to chat clutching feel free to call me tomorrow between 9 am and 6 PM central time and I'll get you taken care of
I should have mentioned this in my earlier post (Sorry Kris).....to find out what you really need/want, call Kris and spend a few minutes discussing your plans, riding style etc.....and he will let you know all of the options available and make sure you are fully prepared to make an educated decision on which route to go.....I don't know too many vendors other than Kris and Alex that will actually email or text their customers months after the sale just to check and see how their doing and if they need any help....that is the benchmark of customer service in my book.
I hate to fall in line here, but I have to agree with above statements in reguards to Kris. He discussed my options with me over the phone, I made a decision and haven't had any trouble for coming up on 2 years now. Very noticeable increase in bottom end power aswell.