I can't speak to amp failures. But if there is widespread reports of amp failures, that is certainly something to factor. Regarding the SW-1600SE vs the RSL 12", even two RSL 12"s is no match for a single RP-1600SW in overall output. The Klipsch 1600 really is performance bragain. But its big, heavy, and possibly has reliability issues, but you would have to look deeper into that.
Also, there is no such thing as a sub being 'too much' for any particular speaker. There can only be 'too little.' Any sub can be level matched to the speakers no matter how powerful it is. The question is, what will run out of headroom first, the sub or the speaker. I think a 1600 paired with the SVS speakers is unlikely to run out of headroom for either for any normal use.