Like Karl I was lucky I didnt stump the cash for the VPM upgrade, I managed to get a loan
of a colour screen VPM unit for a series of 85m dives and was dissapointed at the VPM deco obligation (way more than the bulhmann version I was diving) but the colour scren is excellent.
I also use the 4th option but have had nothing but trouble with the cables on my third one now due to leaks at the Fischer gland and the potted molex end(which ruined the cell)
Pat