I use it quite a bit. APX 400 is a rather inexpensive, but good, 400 speed film. I can still find it in 35mm (Ultrafine Online and possibly Freestyle as their Arista II brand), but can no longer find it in 120 unless I pay for it on ebay. It's a film that never seemed to get popular in the US, probably due to the US being the home base for Tri-X.
I like to use D-76, 1+0 for 9 min., EI 200 with TTL metering. Times off the Massive Dev Chart.
APX400 (new)/Rollei Retro 400 is doing fine in D76. Above time is correct. Dead Link Removed
Best exposure index indeed iso 200-250. This film can have a lot of overexposure without any problems.
The emulsion is still available on 135 micron 35mm material under Retro 400 120 roll film. Especially confectioning in 2006 by Rollei/Maco due to a low APX roll film stock.
These films are widely available (in Europe) up from Eur. 2,85 which is still a pretty good price.
I have a lot of the original APX 100 and 400 in the freezer. Initially I hesitated a little bit to develop apx400 in d76, but I experimented today. Overall I like the results. Thank you.