Having 1.39 for Linux is AWESOME! Yeah, as per a previous post, I'd like to buy you a beer too!
Looking at the new features so far, I'm really excited. I too, dual-boot for the Windows version as well.
I am curious on a few things though (take these as feature requests if not in already, but don't delay 1.39 for these)
--Will it be possible to double/resize the NTSC scaler? What about Standard scalers? I prefer the original look and don't like using the HQ/other scalers that round the original. (I did see your Video TAB screenshot, but only shows Scaler HQ with 3x)
--Will there be the commandline options like in the widows version if there is no gui option (like standard scalers, window size, etc)?