I've had a YQ2 for a couple of years now. At the beginning I found that I was still encountering jams. Now TM seem to have got their act together.
The biggest difference was not in avoiding jams but in knowing how long you could expect to be delayed.
Problem is that my YQ2 is out of warranty and has failed 3 times. TM want £65 each time for replacement or repair so I've binned the little bugger.
My impression of the TM Monitor is that it is a big upgrade on the YQ2 and will probably be more reliable.
Now that I have VDO Sat-Nav, I'm going to get TMC fitted to see what that is like.
There is just one moon and one golden sun; And a smile mean friendship to ev'ryone; Through the mountains divide, and the oceans are wide; It's a small world after all.