I used to think that Kingston was better, but most of the last few Kingston ValueRAM modules I bought had no-name chips with nothing but "32M x 8 -- 7 -- T" printed on them, and some, including those with Hynix chips, flunked both Gold Memory 5.07 and MemTest86 (v. 1.4 and 3.0), even at the slowest settings, unless I slowed the memory bus. All of the bad ones said "ASSY IN CHINA" on their stickers, but so did some of the good ones, but all of the "ASSY IN USA" moduels were good.
I've had better luck with K-byte, even though all of them had second grade chips on them, like Spectec (used, from Micron) or Mystic (Nanya, probably used). One of the Spectecs failed, but all of the Mystics worked. One thing I hate about K-byte is the jerk who answers their phones. Whenever I asked him a question, he'd ask me, "What's your question?" He also tried to BS me, such as by claiming that there were over 10,000 memory chip manufacturers (not memory module manufacturers, chip manufacturers).
Of the brands commonly sold by Best Buy, Staples, etc., in my limited experience the best may be PNY because they seem to always use chips with the brands on them and sometimes get the entire modules from the chip manufacturers. I don't know about overclocking, though.