I choose Option 1 (20 MB) as I'm getting low on disk space. My (only?) disappointment is the start up time it takes BIAB to get going. Time: 1 min 12 sec before it's ready to start. Once it's up I'm ok with the rest of the program.

I'm thinking about switching to Option 2 (20 GB) as I "know" the start time will be faster. BIAB will be on drive C: and RT/RD will remain on the USB. Haven't decided yet.

Cheers