After 35 years of reloading, I looked into/began annealing when my 300 WinMag's brass began to give me loud screeching noises during very difficult withdawal of the expander ball through the neck. As a result I picked up the Hornady case spinner kit/medium-temp Tempilaq technique and never looked back.
Of late I've had to anneal every single piece
of 45-70, 45-90, and 45-3¼ brass that I use w/ Black powder, or the case simply will not seal on ignition (which w/ black powder is hard to ignore). That again involved the spinner technique and again (high-temp) Tempilaq -- and I never looked back.
I spin to get uniform heat application. Pan-of-water just doesn't cut it.
I use Tempilaq to get a specific/repeatable temperature. "Color" and or time alone doesn't cut it either.
Both are simple/non-messy. (Proof: my wife even lets me do it in the kitchen)