I'm a new user so not really qualified to give a review.
I visited the Cycle show specifically to have a play with the Garmin, Memory Map and Satmap products. The new MM unit was a bit unimpressive, looked like it would be hard to operate on the move. But the thing that really put me off was not being able to use it with off the shelf batteries. The Satmap was a thing of beauty, very clear view, very instinctive to use and of course can be used with AAs. But the base mapping wasn't really good enough for anything, I'd want the whole of the UK on Landranger which would push the price to around £500, I just didn't want to spend that much. The Garmin display was impressive, and the staff really helpful, every time I asked which unit would do a specific task the Legend Hcx was in the shortlist, So that’s what I went for. I bought the City Navigator mapping, for on road that's probably as good as I need, for my occasional bit of off road I'll stick with paper maps.
Time will tell if it was the right choice. I'm just getting to grip with the features, so far I've been impressed.