I think Red70 is pretty cool. I've always wondered why Ivoks gets all the attention of the two. The simple answer is probably that Ivoks looks cooler.
In my opinion Red70 works best for bass sounds. Just like Ivoks it's got a nice squelchy filter. The ability to have up to 8 voices, unison, pan spread opens up possibilites that Ivoks doesn't have.
Some synths work really good together with a bit of added distortion/saturation, this is one of them imo.