QB-3, de la Mancha's vintage style EQ is a beauty. It has everything you need to add a nice color to your instruments. Its features are what you would expect from such a plugin and "only" being a 3-band EQ does not make it any less useful. Unlike transparent EQs, I use QB-3 to boost certain frequencies instead of cutting the others, and therefore in a more a creative way.
I really appreciate the 40Hz cut, which helps make room for that kick drum and other low-end stuff and the possibility of typing values directly under the knobs.
Support is excellent and the documentation shows you in depth the process behind QB-3. The price tag, just like all DLM plugins, is extremely affordable.
The presets selection is good but just like presets on any EQ, they will have to be tweaked a little to achieve that sound you are looking for.
Finally, if you like that vintage sound, you could also check out the rest of the DLM vintage series (GTO/GTX compressors and ClipStar), which is just as stellar.