Advanced find in files tools for OS X?
Once you get beyond simply searching in files and enter the realm of doing things like find/replace and file extension filtering, you can't get faster or more extensible than Unix tools like sed, awk, and grep (or ack), particularly when working on hundreds of thousands of files, as you specify.

Bash supports file globbing, so you can easily do extension filtering. Pipe the filtered files into sed for search and replace. I'm not sure exactly what kind of presets you're looking for, but if you find yourself doing the same type of thing often you can put together a script with common "presets".

I've tried TextMate and TextWrangler, and both slow down considerably when running on lots of files. I'd highly recommend familiarizing yourself with the above tools, if you haven't already.