So far I have been lucky and haven't had any QC issues with fomapan 100 in 4x5 (I've gone through 75 sheets at this point).

Sandy et al.,
Here is where I stand. Exposing the film at 100asa, I have found that 13mins @20c with 5s agitation every 30s gives about the best results. All of the shots I took today, I metered using incident readings, and followed it up via spot. All of the negs I tested fell within what would be considered normal development.
The negs have great tones to them, and the highlights look great. However, there is a lack of shadow detail. Im sure that the negative should have it on there, as it fell in zone III, but it just isn't on the film.
Therefore, Im thinking that either 80 or 64asa should do the trick, with perhaps 12mins development time. I'll give it a shot tomorrow and let you know how it works out for me.