Onlywire was great when they offered a free service - i.e. I found their submitter quite flaky and fiddly but I forgave them because it was free. Then they switched to a premium model - and not a very enticing one either. The only thing they have going for them is the number of supported networks.
Hootsuite, meanwhile, I find very stable to use, and a much more reasonable offering unlimited social profiles plus one more user @ $9.99 - which I assume means I can use it to run multiple campaigns across multiple networks. (Please correct me if I'm wrong) The Apps capability also seems to offer potentially as many networks, if not more, than Onlywire - so that seems to be a no-brainer, though even then there's still a few notable absences - namely Delicious, FriendFeed, Newsvine - all of which Onlywire supports, as well as other big bookmarking sites like Digg. (Which neither support for some reason).
I've looked at others and it's pretty much been the same situation, there's always a trade off between the number of users, or network profiles or supported networks.
I'm trying to get the product that offers the best support for all major networks and social bookmarking sites, without limitation, and without costing ridiculous sums of money.
So I'm curious to know which solutions you all picked and why.