I have the MX3 as well. Decent radio with everything I need (and more that I don't use). I'd like to upgrade to it's 2.4Ghz cousin just to eliminate glitching I get in my area and to gain range. The main reason I don't is of course $ or I wouldn't have the MX3 in the first place... plus, I have 3 vehicles so I'd have to buy two extra $90 receivers as well. So, a $180 radio system quickly becomes a $360 radio system...
As it is, I only get about 100 yards of range out of it and I get periodic servo glitching. I think I just have a butt load of radio interference around where I typically run. When I ran up in northern Minnesota at a family visit, I got a lot more distance and virtually no glitching... Maybe it just likes the north?