If even a 1/2 second is way too long for you, you should give up on it unless they release a revised version since a 1/2 second is within their acceptable design parameters with the current version. Hate to say it but you should sell it and start amp shopping, just the wrong tool for your needs.
If you still want Recto tone you could get an old 2 channel Recto and then a separate clean amp and an A/B box to switch between them. You'll have almost the same flexibility and in some areas even more than a Roadster.
Or you could run a preamp into a 2 channel Recto's effects loop for your "clean" sound using just the Recto's power section.
Lots of possibilities.