Over the years (a few decades now) of playing guitar, I've bought and sold so much gear. There are 4 pieces I regret sellling and one of them I really miss still.
Mesa Boogie Mkiv Rev B, as a 19ish year old metal player this was my most expensive purchase but was a true beast.
Mesa Boogie Dual Rec, not sure which revision, I bought it off the UK Marshall rep at the time from his car boot for 700 quid. This was just before Marshall did the DSL/TSL
Boss CE-2, best chorus ever for me. Got it for 30 quid. I love BOSS pedals through and through. Yes, there are some great pedal brands out there but BOSS just do it for me
Ibanez S540 LTD DAB, man I miss this guitar. This is the one I regret the most. The neck was beautiful, the contoured body was awesome. I swapped the pups out for EMGs, 85/Alnico/85. Sounded brutal through the Mkiv and a couple of 1960b cabs. No boosts needed here.
As it is now, I have a Mkiv Rev A, a tatty 1960b, i'll get a CE-2W. However, the S540 is the hardest thing to replace. If anyone knows who has it (southwest UK based i guess) I'd love to see it again lol.