Wow this is a hard question for me to answer.
So I'll break it down this way
1. Thin Lizzy for rock/metal these guys smoked a lot of bands on tours when they did not headline. The best collection of great guitarist in rock history John sykes, Gary Moore, Brian Robertson then to have Phil Lynott on top of all that headliner killer for sure.
2. Mother Finest R&B/Funk/Rock/Metal these guys do it all they have opened up for everyone from Stevie wonder, PFunk, Van Halen, ZZ Top just to name a few and pushed them as hard as any of them could stand. one of the most under rated bands from the 70's who still put music out to this day.
3. Bar-Kays R&B/Funk the house band for Stax records killer players with a take no prisoners attitude and a list of hits as long as the headliners most of the time.
4. Primus alternative/rock before Les Claypool was a household name among musicians. I worked about 20 shows where these guys flat out killed the headliner. High energy and rawness in the early days of that band was just unreal live.
Maxi...................
Bootsy Collins:
I pledge allegiance to the funk, the whole funk, and nothing but the funk, so help me James, Sly and George, Amen!!
Guitars: 2010 American Special HSS Strat, 2010 CIC Squire CV ThinLine Tele, & 2006 MIM FSR Strat.
Basses: 1979 Peavey T-40, 2007 Ibanez SR 500, 2013 Ibanez SR375F, 2013 CIJ Fender Geddy Lee Jazz Bass, 2014 Sadowsky Will Lee VI, & 2014 Sadowsky Will Lee Metro V
Amps: Mesa Boogie BASS STRATEGY:Eight:88, Aguliar DB 4X12, Augilar DB 751, Genz Benz CTR500-210T/Focus 1X15 CAB, Fender Hot Rod Deville 410, VHT Deliverance 60/VHT 2X12 fat Bottom Cab, & VOX DA20
Effects: Boss ME-25, MXR Custom Baddass 78, MXR Custom Baddass modified O.D., Vox Joe Satriani Satchurator, MXR Phase 90, MXR Bass Chorus Deluxe/Octave Deluxe/Bass Compressor/Envelope Filter/, Way Huge Pork Loin