Why not get just another Quark mini-AA? They had limited edition of high-CRI version but that seems to out of stock already. They still have Mini 123 and CR2 version available.
A UF-2100 is huge compared to a MiNi AA. (which is what the OP is looking to replace). To me the E03 is even a bit on the large side for sitting in a pocket but the output is equally large. I’d just get another MiNi or equivalent.
All ITP lights uses premium tints (white). I have Xeno E03 CW XML, and I can say that it's not so cold, only a slight purplish spill tint (outer part). Both ITPs I have has very good white tint. Anyway, how much do you want to spend?
yeah I agree vs the a3 sized lights.. but the uf-2100 isn't much bigger than the balder that's being mentioned..to my benefit I was at work and posting lol (and busy doing so)..I like to mention the 2100 when I can..def worth a look for a pocket rocket..I know my 14500 lights have been sitting on the table since i've received the 2100..