I have two of the Array 3723A loads, both with the optional GPIB interface. One is about 5 years old and I liked it enough to buy a second one earlier this year for some dual-rail supply testing.
The 372x series does not appear to be based on those tired designs that get copied between BK, Maynuo, and ITech. I've only seen Gossen reselling it, as you mentioned.
The fans are thermostatically controlled, but they are not "whisper quiet" when the unit is turned on and they get louder from there as it dissipates any significant load.
The GPIB and RS232 (and optional USB which I don't have) all support SCPI which I've used quite a bit. I haven't found any bugs, which I can't say about other loads I've tested in the past (BK, Aim-TTi). All the interfaces are isolated (no isolator/level translator dongles like some of the BK units).
I've found it easy to setup and use. The menus are simple and logically arranged. The loop response is excellent and I've never had it oscillate (although given enough time I could probably find some conditions that annoy it). I really like that all the connections, besides computer control, are accessible on the *front* (duh).
Both of my units have been performing well with one minor exception. The older one seems to have developed an intermittent issue over the last year or two with, I think, the remote voltage sense relay inside the unit. The display was showing close to 0V when there was quite clearly more than that. Cycling the relay by temporarily disconnecting the remote sense terminals cleared the problem. It's only happened a few times, so I haven't been able to track it down definitively.
I've posted a bunch of times about this load if you search for "site:eevblog.com array 3723a". Internal construction is solid, commensurate with the price in my opinion. There's some internal photos here:
https://www.eevblog.com/forum/testgear/any-experience-with-scpi-and-chinese-dcprogrammable-loads/msg352717/#msg352717