Yeah... It would be nice to have for 20V too.. but the only way now is to DIY a transparent window.
Btw, try imagining how cool it would be to have a transparent valve cover as well... I think Lexan should be able to withstand the heat... but not too sure about it.
There are quite a number of boost controllers available in the market. Perhaps I would list down a few such as HKS EVC, BLITZ Dual SBC Electronic Boost Controller, Apexi AVCR Boost Controller, SARD...