On Original Topic- If you wish to load 10mm to anything vaguely like its potential, that is a niche requirement, that won't be suitable for .38spl . If your 10mm reloading requirements will be sufficently covered with loads not much different from top end .40s&w , then the above quoted powders.

In General - If old guys and those mentored by old guys swear by Unique , then middle aged guys, and those so mentored will swear by 231 .

But despite the old guy love , Unique remains the most versitile and flexible powder. Dirty ? Clean your gun every 3-400 rds , and don't obsess. Metering? Not the worst, but subjective to your priorities .

Revolvers are more forgiving of powder selection. (Excluding magnum level compressed loads) , revolver loads simply need to not exceede max pressures, and burn reasonably well . Case capacity is rarely an issue of having enough room. Semiautomatics have concerns with pressure curves for cycling, and sufficient density .