I'm not sure what you guys do with your cars, but if you're needing shocks every year or two it's clearly more than I'm doing with mine. For my 5 or so track days per year, annual pilgrimage to the twisties (about a 1000 mile trip, half of which is deserted, entertaining roads), 5k or so of daily driving, and every so often major road trip west, it sure seems like I ought to get a few years out of a set of even average performance shocks like Bilstein or Koni. And historically, I have.
As for MCS and AST, I thought we were talking about race car parts now, with race car maintenance? Which I have zero interest in. It also strikes me as GC would be more fussy in that respect, since it's not really OEM-replacement type stuff. If all I did was drive around town and to and from the track and had time on my hands to pull my car apart every other month, hell yes. I'd call Terry tomorrow (or after my Christmas bonus comes through, anyway) and get my MCS setup in motion. But on a long road trip I just need stuff to work, and what goes on my car needs to be the kind of parts I don't have to worry about when I'm 2000 miles from home.
I think we've got diverging interests here, in terms of what we are talking about. As best I can tell, the ST/KW stuff, Konis and Bilsteins (and Tokico, FRPP, etc.) generally fall into the OEM-replacement category in the sense they're designed for long-term use on the road or track with no real maintenance required. Then you've got the high-end stuff that's a little more fussy, in AST and MCS (and GC, if I had to guess), but is significantly higher quality in the sense that it performs its function in a superior manner. For the OP, and for my own car, I'm in the former camp. A number of you are in the latter.
I think there is a gap in the market for a damper between Koni/Bilstein and AST/MCS. If Bilstein would make a rebound adjustable damper with properly welded strut tabs (if that's actually a recurring issue), there it is. And they wouldn't need to charge $2600+ for a set of those, I don't believe. Probably won't happen, and so be it.
Additionally, even if I didn't ever track my car, I can and do benefit from adjustable damping. Adjustable damping isn't just about adjusting handling balance at the limit. And in my experience that's actually a secondary (or even tertiary?) function of adjustable damping. The first is to adjust the shocks to that sweet spot where the car is well controlled and responsive in aggressive driving yet not so harsh as to be skipping over bumps and losing contact with the pavement. Generally speaking, I have to drive a long way to get to twisty roads from the KC area. So I run shocks fairly soft or full soft on the interstate getting there, and then dial them up when we get to the good stuff. I don't believe that's unusual.
Anyway, some good material in this thread, and I'll certainly be more conscious of the fact that my Konis may well not be as bulletproof as they have been for me historically. To the OP, I'd say the XTA setup sounds great, provided you don't mind being fairly low and you don't mind the possibility of a few squeaks and clunks here and there from the camber plates. If the Konis fail on me, I'll likely move to the KW V3 topped with the Steeda upper mounts and see how that goes. If I can get an ATS-V for my wife in a few years and use it as my road trip car, then I call Terry and properly dedicate the Mustang to the track
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