During the cathod ray tube era (CRT) where the picture is created literally by scanning lines that move across the screen really fast, because most PAL transmits at 50hz (exept in Brazil which is PAL-M 60hz)the picture appears to flicker more than NTSC 60hz which if you are not used to it, it could cause headache. I hate PAL at first because of too much flicker but as more games that I played are in PAL I eventually got used to it and don't notice the flicker anymore. LCD TV don't flicker so you don't notice the disadvantage of PAL but you still see the advantage of PAL over NTSC which is better resolution. So when it comes to LCD monitor, I prefer PAL over NTSC but during the old days where CRT TV was the standard, I prefer NTSC than PAL because NTSC is 60hz so the picture appears brighter and have less flicker. But this advantage is off by 20% picture resolution when using the same bandwidth of electromagnetic spectrum that is why PAL have 625lines while NTSC have 525lines.
It's great