2David Graser: hi
I'm using
ifs=d:\os2\boot\fat32.ifs /cache:2048 /h /ac:* /largefiles /fat /exfat /eas /plus
call=d:\os2\cachef32.exe /f /p:2 /m:50000 /b:250 /d:5000
As far as I can see this is almost the same settings as you have, except for "/fat" for FAT12/FAT16 support, "/exfat" for exFAT support, "/eas" for EAs support, and "/plus" for support of files whose sizes are larger or equal than 4 GB. These are very useful switches, if you don't know. Also, I don't use FM/2, but use FC/2, I have a 1 TB FAT32 USB drive -- it works relatively fast (only needs to spin up first, as it goes to sleep usually). My 128 GB microSDXC card works fast too -- they both reread in a second or so, not 40 seconds, as you report. So, it is probably, specific somehow to FM/2, I'd suppose.
PS: Also, AFAICS, WPS opens these 128 GB and 1 TB drives faster than 40 s. It scans all directory structure for about 10 s (folder view), but just opening an icon view is fast -- 1-2 s. FC/2 does not scan whole directory structure each time, but FM/2 probably, does.