OK, acquired LongShot powder. Is very similar (size) to Titegroup and meters VERY nicely in my 550B. Built 100 rds at .2 gns over minimum recommendation.
Report as soon as I shoot them. DOES meter nicely. bunch of guys at TheHighRoad said if I've been using TiteGroup/Unique/800X for pistol powders, Longshot will replace them all and put big smile on face!
Let ya know!