I fall into the category of "power user" but I find Alfred redundant because I already know my way around OS X. Customising Alfred with workflows just takes up extra time for me, usually with little good reason. People rave on about workflows but on the rare occasions when they actually try to demonstrate why they're supposedly useful, it rapidly becomes apparent that it's just duplicating functionality that can already be quickly achieved some other way.
For example, one guy was saying how he uses it to quickly VNC into other Macs. Well, you can already do that quickly by hitting Cmd-K in Finder where you'll find a list of your common connections already stored, so manually updating these in Alfred just to save a one-millisecond keypress seems pretty pointless to me.
A couple of other people have demonstrated workflows which show your current battery life. What's the benefit of this when that information is already present in the menu bar? Some others have shown how they've painstakingly set up workflows for searches on specific websites. Why bother with that when there are quicker ways of achieving it in a web browser which don't require any faffing about (e.g. Safari now remembers sites you've been to which have search engines, so for example you can search for The Terminator on IMDB simply by hitting Cmd-L in Safari and typing "imdb terminator").
If you're new to OS X and haven't learnt the quick ways of doing things which Apple have already provided then maybe Alfred gives a handy shortcut if you can be bothered to spend time customising it; but otherwise I consider it surplus to requirements. For finding files, launching apps, and other similar quick tasks, Spotlight does the job well.
