I actually have a similar 2-in-1 Rat-Screamer pedal in the guise of Magnetic Effects’ 2020 limited edition Dual Drive. In both cases you have separate Channels with Rat and TS808 flavours - both I believe TS808 > Rat. While the controls are slightly different - with this Science Fair having universal Level and Blend controls, while the ME Dual Drive has independent Volume, Tone and Gain knobs for each side. There are advantages to each approach.
The Magnetic Effects Dual Drive obviously has more tonal variations, while the Science Fair delivers more granularity in mixing up the two sides.
Controls - Lab Rat Side } Drive, Tone, Test Tube Side } Drive, Tone, Universal } Volume, Blend.
I feel that the simple graphics and bright colours really suit this format and the Science Fair is a very smartly calibrated affair - very reasonably priced at $164.99 - courtesy of the Summer School Electronics Webstore. These are in high demand currently and actually sold out right at this moment - while you can pre-order one on the site - for delivery before March in theory.
This is for sure a really nice-to-have pedal for me - where I’ve yet to assign any sort of priority to it. Still deciding on how much use I would have for it.
In any case I feel that conceptually and execution-wise this is a really nicely realised pedal at a very decent price point - that deserves to do well!