I'm ready to jump on a Dr. Z RX ES head, but I'd really like to know what competes with it in terms of price and sound. I think $1600 is a great price compared to some of the other boutique amps out there right now, and the sound really fits me. But at the same time I'm very interested in trying out the 65 London and maybe the Tophat King Royale, if I can find either of those. I've heard excellent things about the London and have the urge to give it a shot. Are there any amps I should consider before buying the Prescription ES? Please help!! I also really don't want to go for anything over $2000, but I'm willing to sacrifice more cash for more tone.