So far I have only been testing games for a matter of seconds or minutes, mainly to check after doing work on the motherboard that things still work ok, so only seen some of the games in demo mode so far (look fine), like Gradius. Also can't play the games at the moment as the controller is taken apart and not connected.
There have been many posts, some contradictory, about speed difference in real terms between the PAL TurboGrafx and the PCE. Logically, working with a slower clock rate will have an impact on the game speed, however, as was pointed out by someone, the refresh rate is also lower by 20% so therefore the impact may not be too obvious. Hey, I don't know yet, you guys have been playing your systems and know the subject far better than I do, so I am sure the PAL one does work slower, however proof is in the testing. If I find the PAL system runs juttery, I may dive my hands into my pocket again and get a PCE, however, if the PAL system runs perfectly fine, there is no point. My motherboard is trimmed and separated from its case, so which version of the hardware or colour of the box is not important; its how it plays the games.
What I do know, is that when I get the system working properly, I will test each of my 25 or so games I currently have (about 70% are Japanese ones) and let you guys know if I see any slowdowns in the games or not (especially when there are lots of sprites on the screen), and if they are minor or a pain, or not noticable. If the whole game runs slightly slower but without slowdowns, I will be happy with that, because, to be frank, I will do far better in action games than I normally can!