The hard drive isn't all that hard to replace there are plenty of instructions on the internet.
Its such a shame people actually look to the Apple Forums for advice, they seem to be just one-way rant-boards with no discussion.
Without meaning to sound really rude it sounds like you are pretty set on not buying an iMac, every commenter on this thread has tried to reassure and i'd imagine most (if not all) of us actually own one of the things. I'm not sure what you expected us to say to change your mind? If it bothers you that much just go for the Mini they're still great little machines, if not quite as good value for money
Sorry I thought the hard drives in the 2011 iMac had a proprietary connections?
I honestly haven't made my mind up one way or the other and you aren't being rude I know I'm being incredibly indecisive