Not meaning to bog this down as we needed the Advanced Search feature and are glad it`s now implemented, but the search speed is slower than it was on SM15 and much slower than it is in Outlook when searching in all mail items for the same key words. I know you can fine-tune the search, but sometimes you simply do not know who sent you that mail or when, etc - just know 2-3 key words from the mail.
I can see that most people are complaining about the SM16 interface speed, when we are OK with that - but now we are complaining about the Search speed :)
Also, please do not forget about trying to improve the feature`s accessibility by making it more obvious for users where it`s located and by allowing to start searching for a search string directly without having to select anything from the drop-down lists, unless you know you can tune the search.