For me, what puts me off exchange is the silly licensing scheme. You have to get Server Cals and client Cals which have to be updated if you change your Office version - like I don't have anything better to do with my time lol. I was referring more to the difficulty of exchange for small clients. Its a bit overkill for clients who only have two servers.

I also don't want exchange to tie me into just outlook. This product I mentioned supports phones, ipads, thunderbird and outlook as well as web. A winner for me all round.