I bought a Cascade Fathed to get some ribbon mic mojo going on at home, based on Leon's suggestion. Eventually I will get a 160. I already had a Sennheiser e609 which seems to cover the 57 style response pretty well.
I find that you almost don't need to use bass/treble cuts on the cab block if you choose the right mics. 57 at 0dB, then bring up the 160 level until the lows don't sound thin. Usually around -7db gets 'er done. I also add a room mic, down about 10-13dB, to pull the amp out of the monitors and into the air. In addition to the mix levels, I tweak the timing so that the 57 and 160 both have the peak of the initial transient at the same spot, and the room mic transient is just a hair later. Most of the IRs set for MPT are pretty consistent in the timing, so I end up with 1.7mm on the 160 and 8.5mm on the room mic most of the time with OH, RedWirez, and others. I guess the algorithm that does the MPT file trimming is pretty consistent.
I have been taking these mixes into Cab-Lab 3 and turning them into single IRs, to save CPU percentage. I wish that Cab-Lab 3 had the same measuring units for the mic delays, though. It's hundredths of a millisecond in Cab-Lab, vs. mm of mic distance in the AxeFx3.