PSP ClassicQ is inspired by various classic British-style equalizers. It captures the sound and flavor of famously musical high and low filters (such as those in early Neve EQs), melded to very precise mid-range filter. In addition, PSP ClassicQ offers a selectable simulation of class A circuitry and output transformer for a unique, vintage-style color. To its classic features PSP ClassicQ adds extremely useful features such as an adjustable high pass filter, switchable Q for low- and high-shelf filters, and a sweepable midrange bell-type filter. The design of PSP ClassicQ lends it especially well to fixing and shaping individual tracks. 

PSP ClassicQex is extended version of the PSP ClassicQ. All features of the previous version are available, and a new Low Mid section is added.

Yes, there are a lot of EQ plug ins out there. But PSP EQs have good sound at a very affordable price. Add to it the fact that the limited frequency selection some titles narrow 'the world of endless twidlling', forcing you to pick a frequency and move on! - just like many of our analog consoles. (...) I wholeheartedly suggest readers try the free demo available from the PSP website.
Garrett Haines, TapeOp

Most DAWs already come with one or more equaliser plug-ins, but PSP equalisers do manage to capture that elusive warm and cuddly analogue vibe, and that's what you're paying for here.
Paul White, Sound on Sound

Four distinct flavours of EQ. Stunningly combats digital sterility. Beautiful interfaces. Easy to use. Light on your CPU.
Computer Music, Music Radar