Almost everything you read in these forums is opinion. Sometimes it's opinion based on first hand experience and other times it is just opinion.

I have two 2-stroke engines and three 4-strokes currently on planes. All of my 4-strokes (OS & Magnum) seem to run consistently throughout the range of throttle settings. They idle forever if I want, and transition from idle (or any low setting) to a higher setting is always smooth. My 2-strokes are less consistent. My TT-61 Pro idles great and runs great at full throttle. Transition from idle to full is pretty good but not great. It tends to "gurgle" at part throttle and transition from a low setting to a higher one is usually not smooth. I have an ASP 61 and it seems to throttle better than my TT and it does not "gurgle" at part throttle. The ASP is pretty new so only time will tell how well it works long term.

Since the Showtime appears to be something that would need to run at lots of different throttle settings, my opinion based on experience with my own engines is that a 4-stroke would be a better choice than a 2-stroke.