I switched to DuckDuckGo for search for one of the reasons you listed - Google felt the need to guess what I was thinking and it felt like, most of the time, it was getting it wrong (especially with synonym search). One of DuckDuckGo's stated policies is not to modify what you search[0]. The fact that DDG doesn't collect information about me is just a plus.
I tried to do the same after upgrading my Linux Mint but I couldn't resist more than a couple of days, maybe I'm too used to Google UI..
but I agree with some of the comments, sometimes I know I should search something on Amazon, Wikipedia, iMDB, Tripadvisor etc.. and I just use Google to go there (because typically if you search a movie iMDB is one of the first results, if you search "hotel xyz review" you got Tripadvisor etc..)
[0] http://help.dukgo.com/customer/portal/articles/215637-autoco...