TipTop's Z4000NS gives you CV control of all four stages of the ADSR at a street price of $175US. I have a couple. They work as advertised. The Doepfer A-140 doesn't have CV control of parameters.
The Befaco is actually quite nice, as there is also a gate output that fires off for EACH stage of ADSR. That could be useful for triggering other modules, sequencers, or ADSRs.
I would want one or two "Gucci" ADSR units for complex envelope generation. Then less expensive BASIC ADSRs if I need more envelope generators that are just doing what's labeled on the tin, like the Doepfer... as they are half as expensive.
I'd buy at least one Befaco if I was doing it again. I find the extra gates per stage to be hella' useful.