I've just noticed that many of the Glock challengers that have released in recent years feature a fully cocked striker (P320, VP9, M&P, PPQ, etc). I imagine that we don't see many partially cocked designs due to Glock patents (we probably wouldn't even have the M&P without the Glock patents, considering the Sigma episode). But if you're going to utilize a fully cocked striker (essentially a SAO design, right?), I figure you might as well get a noteworthy out-of-the-box trigger in the deal.
I'll admit that I am not entirely at ease with some of these fully cocked designs, but I'm also satisfied with OEM Glock triggers.