I seem to have had the same experience as most people here, on the whole it works fairly well and is easy to use but the results can be hit and miss. The most common conversion I do is from V4 to Dawn (now there is a surprise) and it works most of the time. One issue that does come up is anything that goes closely around the neck such as a bodysuit as it appears to come out badly twisted, this appears to be because Dawn has a neck 1 and neck 2. The neck problem can be rectified by twisting one of Dawn's neck section until the twist straightens out.

This is the Spartan Ops for V4 which is a mixture of conforming and props, the bodysuit and the boots being conforming. The body suit did have the neck issue I described above but on the whole the boots and suit converted well.

This was a render from 2017 so a little dated.

 

 

I use Poser 13 on Windows 11 - For Scene set up I use a Geekcom A5 -  Ryzen 9 5900HX, with 64 gig ram and 3 TB  storage, mini PC with final rendering done on normal sized desktop using an AMD Ryzen Threadipper 1950X CPU, Corsair Hydro H100i CPU cooler, 3XS EVGA GTX 1080i SC with 11g Ram, 4 X 16gig Corsair DDR4 Ram and a Corsair RM 100 PSU .   The desktop is in a remote location with rendering done via Queue Manager which gives me a clearer desktop and quieter computer room.