Thanks Muttley, I also have a 289, its a few years newer than my 189 but the 189 seems to have drifted less than the 289. Both killer handheld DMMs for sure. I have a UNI-T un171b on order as well, just wants something not as valuable to toss around. I had a HP 34401a 10 years ago, paid $250 for it and it was like new (surplus Gov contract deal). Like a fool I sold it when I moved to a new job and state. I dont need a 6.5 digit .0035% DMM, and its just a hobby for me, so the SDM3055 should work out well.
I've warmed my room up a few deg, it seems the meter and voltage ref are now within one digit, cant ask for much more than that. One thing I forgot to mention above, the fan is not a bother at all, very quiet.