I'm using a Line 6 POD HD Pro as a preamp / FX unit, into a Marshall 9005 power amp, for the role of Dave Murray in an Iron Maiden tribute band I just joined. (My first gig with them is in a couple weeks; I'll probably upgrade to a JMP-1 and TC G-Force after a few more gigs, but this setup is working pretty well so far.) For a couple of my lead patches, I deviated from "canon" and based them off the Soldano SLO100 model for that high-gain, creamy neck pickup sound Dave uses. (My rhythm patches are based on JCM800 models.) Other lead patches are JCM800 with compressor, "Tube Drive," delay (different settings ranging from around 130ms to 390ms, depending on what I need it for - fast to help fast legato runs or trills sound faster, long when I need lots of sustain like for the "Run to the Hills" intro), and phase (0.3 Hz speed) & wah that are off by default but can be switched in when needed. For the first lead in Powerslave, I used the SLO100 patch with compression, delay (261 ms, one repeat), and "Script Phase" (Phase 90) at about 0.5 Hz speed. Here's me testing it out when I was first dialing it in, prior to my full-band audition; there was still a little tweaking to do in this clip and my playing has gotten better since too, but it was pretty darn close here. Don't forget the noise gate effect as the last part of your signal chain before the power amp - for any of your patches, clean, crunch, or high-gain. Makes a big difference.