R422 forces PAL60 which isn't the same as NTSC, same output frequency but different color signal. Doesn't matter if your TV is PAL60 compatible though.
Don't bother with R422 unless its a non-PAL Dreamcast, pop in the 4 wire chip to bypass region protections. The region change mod won't do any good unless you want to permanently make the swirl orange for a PAL Dreamcast. But if you do the region change mod for the love of all things holy don't leave the 12v wire connected when you are done! It'll cook the flash rom chip rendering you with a dead DC.
A few fries short of a happy meal.