The search engine is really pretty good, although there are aspects of it that aren't as good as the old one, there are a lot of things that are better. The big problems have been when the indexing failed.
I'm just choking on this one - have you tried to search within a thread lately? You get the thread returned and that's it - IOW it is totally and completely useless - not sure what you're searching or using but it is unlikely to be the crap they recently installed.