I'm running an alpine h700, so I don't think its overkill at all
I'd just run it before (2ch), seeing as running it after would be useless to a certain degree (unless your heavily overlapping your tweet/mid crossover). Say you cross your componets at 6khz. Your bands up to 6khz will effect the mids almost entirely, and the bands above will only effect the tweeters. Thus why you shouldn't bother running it after. You'll save a lot of CPU cycles this way as well I would think.
PS i'm a car audio guy