Hi Ricardo,
I have a couple of years' experience using the Aspen on a Cessna 421. Overall, I would say it's a powerful piece of kit for the money.
Sometimes it can be a bit fiddly in flight due to having packed so many functions into such a small box (for instance, pressing the selector knob one too many times and watching the alt bug disappearing up the tape rather than the heading bug that you were meaning to change!), but nothing that would make me say no to it. It also integrates with a lot of different legacy avionics quite nicely.
The only problem we had so far was that one of the selector knobs failed after a couple of hundred hours, but it was replaced under warranty.
Hope that helps. Rich