my opinion
Is QV and Tornel. Good results with both of those. Just watch out for the fake QV products that are starting to float around now. It was verified on another board. Don't remember which one it was, maybe somebody else knows more about the fakes?
Brovel turned out to be junk for any of their products that I've tested out over the last few years.
Also, Tt is done, don't trust any of their products out there now unless you know EXACTLY what to look for in the fakes.