I own both. The NH35A is made by Seiko, that I do know and the SW200 is a Swiss made movement, has been for years. The sweep of the second hand in the SW200 is superior to the NH35A also, its far smoother running imo.
I own several SW200 watches and I love them. Its a solid movement so far with a really nice sweep. I don't own a NH35A but would like to if a good deal comes along. I've only heard good things about the NH35A. I guess it would really come to how much are willing to spend but it doesn't seem like you could go wrong either way.
The SW200 auto is very popular and the NH35A is as well. If you had to have one or the other regulated you could take it to any good jeweler and have it done with no problems. I have a 9937OB Ive worn for well over a year and never had it regulated. In fact it is still running + 3-4 sec off the Naval clock consistently. A great movement for sure.