I purchased Wasp as a Fruityloops add-on. The VSTi is mostly similar with added effects and well designed presets. To FL's credit the upgrade was free.
I like the built in effects and EQ. The organized presets are good jumping points for programming your own sounds. In this sense it makes working with the interface less difficult. That said, I have never liked the interface and after a couple of years still don't. Although simple in my very subjective opinion the UI is unintuitive.
In general the Wasp sounds hard although it does a good job with pads and can sound warm especially when using the EQ. Pads are good but lack a certain character that is found on other synths in it's price range and below.
Amplitude envelopes are a concern. Moderate release times create a lot of CPU load. They stay active well after any sound is audible (and well beyond when they should have faded). Compared to other VST instruments this is a serious issue. In general CPU use is substantial.
In a test Reaktor running Dash's daVectorFX Wavestation clone (a fairly processor intensive ensemble) took up less resources. Three instances of Pentagon 1 took up the same resouces as Wasp playing a 3 sustaining notes. You get the idea.
This isn't meant to slight Wasp VST but it seems odd that most of the VST instruments I have are more efficient with resources.
So, where are we? I like Wasp's sound and use it occasionally in Orion Platinum - this version has better filters, envelope setting and tons of useful patches. Still the value for money for Wasp VST is reasonable. Although I am not a fan of the UI Wasp still delivers sonically.
Docked stars for CPU useage.
Check this synth out, it has a good range of timbres for a reasonable price. If you have a fast computer the resource issue probably won't be important.
Freeware is catching up to this venerable synth. Try Synth One as an alternative.