According to Wikipedia, Neon was literally the very first VST synthesizer, not the first software synthesizer but the first one made using the Steinberg VST standard. I don't know how well it compared to the competition in '98 or '99 but the synth is now freeware as part of the Steinberg Classics Pack Vol. 2.
Sound-wise, it's a thick and bland sound, not necessarily bad-- in fact, I'm sure you could imagine places to use it but with such a wide variety of free synths out there, why would you? The timbral variety offered by the Neon is paltry, mostly due to a filter that doesn't filter very much and a hard-to-hear LFO.
Capable of a count-them-on-one-hand number of appealing sounds.
Unbelievably low CPU usage. On my laptop which is from 2008, it used 0.1% of my CPU.
Badly implemented skeuomorphic knobs require you to point your mouse in the actual direction you want to turn your knob.
Filter and LFO are both difficult to hear.
Extremely low timbral variety.
If you're actively looking for an uninspiring synth, you've found one. Otherwise, the value of this VST is extremely limited.
Some great memories of this synth so it has a nostalgia factor... But most of all I seem to remember thinking "DAMNIT, FILTER, OPEN!" because it seemed to be impossible to get the cutoff to go very high at all.
In the manual it states "The Neon is polyphonic with up to 16 voices. However, since each added voice consumes CPU power, the maximum polyphony may be limited by the speed of your computer."
However I can only get 5 voices out of it. Is it inaccurately determining modern CPU speeds or did they outright lie all these years? Oh well, it's a piece of crap anyway. The CS40 actually has 8 voices but it's advertised as "polyphonic with up to 6 voices". Nothing but lies.