I've also done this EQ matching but I do it a bit differently:
1. First I'll try to find out what gear the guitarist whos sound I'm trying to get close to used in the studio. This works as starting point.
2. Next I'll need the original isolated guitar track for the match eq.
3. Then I record myself playing the same riff and compare what kind of eq'ing I would need to get closer to the original.
4. I'll try changing cab and mic, and record myself again to see if I'm getting closer to the original.
5. I'll try changing amp controls, maybe even amp if needed, and record myself again to see if I'm closer to the original and what kind of further eq'ing I should still do
6. At this point I'll add PEQ to the signal chain after cab and fine tune what ever I'm still missing
That's it. This may not get you there all the way but imho it gets you close enough and you don't need to use user IR slot
Also, while I'm recording the target riff (original) I'll try to monitor visually how dynamic it is. When I record my self I'll try to see if my signal chain needs compression to get dynamics about to the same level. Like mentioned before, matching EQ only gives you the tone but you still need to figure out dynamics, the feel, drive, etc. IMHO those are equally important as the tone. All matched IRs that I've tried (haven't tried the one in this thread) first sound great but when actually playing with them longer I get bored really quickly because they don't feel right (for me).