LeviathanKiller
Knee-shooting Archer
Rosen's revamping of the NadIR loader is probably the most recent free IR loader so it's a good choice IMO.
As far as actual impulses go
SinMix has a good one here: http://www.sinmix.pl/free-stuff/ (scroll down to free IR named SinMix_Mesa57_IR.wav)
Here's a few others: http://bedroomproducersblog.com/201...6-best-free-guitar-cabinet-impulse-responses/
Ola Englund has a good one somewhere on one of his videos too I think but I can't find it right now
As far as actual impulses go
SinMix has a good one here: http://www.sinmix.pl/free-stuff/ (scroll down to free IR named SinMix_Mesa57_IR.wav)
Here's a few others: http://bedroomproducersblog.com/201...6-best-free-guitar-cabinet-impulse-responses/
Ola Englund has a good one somewhere on one of his videos too I think but I can't find it right now