I bought an HE a couple of months ago (before the price dropped) to replace my Tusa IQ 700 (same as a DR Duo) which turned into a bottom timer/dive logger as soon as I added a 3rd gas. I looked at and really wanted a VR3, but it was hard to justify the price difference for the diving that I will be doing for the next few years. The downsides of the HE are that you must reprogram your gases every day (it resets at midnight like your Duo), you can't turn off the audible alarms, the downloader is clunky, it is picky about gas switch depth and if you get locked out, you are locked out for 48 hours. For the currect price, it is hard to beat if you are looking for a trimix/multiple gas computer.
Jackie