I have both the explorer (about 50 trimix dives on it) and the latest VR3..
I haven't had any real problems with the explorer, some minor issues all were fixed with software upgrades. If you don't have at least version 1.16 (current is 1.18) I would get it upgraded (free of charge), much better on power and some other enhancements. I actualy had 1 of the first computers shipped (version 1.06, then updated to 1.12, now updated to 1.18), I received it last february and am satisfied. I just got the new VR3 and haven't dove it yet, the earlier VR3 had lots of problems.. I ALWAYS cut tables (worst case) but like the freedom of running a computer profile especially multilevel dives but don't dive past my bail out tables.
I love the buttons on the explorer when in cold water they are the best, but are a bit unconfortable for the few few dives in warm water without gloves.
Their turn around (for upgrades) is not the greatest, but The size of the display on the computer and the features can't be beat. I have used it both on open circuit and closed circuit rebreather dives (many of the bugs were in the RB functions).
If you haven't been told, put a small dab of conductive grease on the battery tab, there have been a few instances reported that computers have reset underwater, This is a slight possibility when water temp changes drastically since the case is made out of lexan and the tab is metal, also be sure to follow the manufactures recommendation on installing the battery cap, THIS IS THE SINGLE MOST IMPORTANT THING TO REMEMBER. Improper installation of the battery (over or under tightening) can also cause the computer to reset as pressure around the computer changes.
Dive Safe
Joe