I am using
www.link2exchange.com right now. I switched to them from exchangemymail because EMM would not help me try to get Apple Mail working with the BES, and link2exchange was willing to do anything they could to help. After a couple hours of trying different settings, which I got from their 24 hour tech support line, I got it working! So, this kind of dedicated support leads me to believe that they will do whatever needs to be done to get it working for you. Really, it shouldn't be that hard. As long as you have TM Enterprise, and not Professional, it should work with some pretty standard settings. TM Enterprise supports Exchange accounts, and a hosted BES is really just utilizing an Exchange account and syncing it with the BB. So what will happen is that your TM will not be actually synciung with the BB directly, it will be syncing with the Exchange server hosted by link2exchange, and the BB will also be syncing with the Exchange server. So everything ends up synced, just through the Exchange server at link2exchange.
Also, TM can directly sync with the BB through a USB cable. I tried it a few months ago just for the hell of it and it worked. It will actually load new icons onto the BB, one each for Matters, Contacts, To Dos, Calendar, etc., and it uses TM specific icons so they stand out real nicely. I don't know about whether you can sync those through the BES, but I just wanted to let you know your options.
BTW, if you go with link2exchange and it for some reason does not work (which I doubt), they will refund your money within 30 days of starting the acct. Let me know if you get it working. As a new attorney I really need something like this so I can utilize my two favorite tech items - my BB 8700c and Time Matters!