Every rally Evo and Subaru here has antilag (running Motec, GEMS and the like) and they does not change turbos every race. It's more like a turbo for a season, which is a few
really hard thousands km. Ah, and they run stock turbos.
I guess you overestimate the load ALS puts on the car.
My mates VII has made 1.5 rally seasons without changing turbo, manifold or anything engine related. It was running 29 psi peak boost and ALS all this time and it would still be fine now if not crashed.
The first O2 sensor (in the header) yes, this might die prematurely. Aftermarket ECUs don't use it anyway.
Going back to the topic, I'm myself very interested in AEM "rally-style ALS". Here we mostly have Motecs and GEMS which are much more $$$$ than the AEM EMS. If it's possible to run a real ALS on the AEM, it'll be a nice alternative. Googling around gets me a couple of threads here and there with people saying "AEM rally antilag isn't really working" or "AEM rally antilag can be done, few tuners done that", but no details and no success stories. So if anyone has AEM EMS rally style antilag running I'd very happy to hear