I've been shooting Fomapan 100 in 4x5 for last few years with D-76 1+1 as a developer. I haven't tried any other developer, but to be honest I wouldn't expect too much. Fomapan is just OK for me - nothing more, nothing less. In 120 format I use FP4+/HP5+ with D-76 1+1 and I love them. If the price would not be the key factor, I would do it also in LF. In Poland, where I live, price of FP4+ per sheet is almost 3x higher that Fomapan...