Well, it's certainly good that he's changed this. Hopefully it's sincere. This was honestly one of my biggest qualms with the Donald.
I don't really understand how being a "flip-flopper" is a bad thing.
It's a question of judgement. How do we know he's not going to flip-flop on everything else?
When you run for freaking
President of the United States, you should already have solid positions on most of the issues. Trump doesn't. Of course, this isn't the most important thing--I'd vote for a flaky libertarian over a solid statist any day--but it is a very important issue.
If he needs research to get that killing innocent people because their parent/spouse is a terrorist is, you know,
wrong, I'm very wary of what he might do as President.
Not all flip-flops are those kind, however, the kind where they genuinely didn't know, did research, and learned. Some flip-flops are the kind where they look at the polls and change their position--like Hillary Clinton, who supported "traditional marriage" before popular opinion changed, now she's acting like a freaking gay rights pioneer. Honestly, this is the worst type of flip-flop.
While I'd rather vote for an honest expert, I'd vote for an ignorant person like Trump over a liar like Clinton