I really can't say because I'm sure you'll get reasons why they're 'good' and why they aren't. BUT, that doesn't prevent your bro' from doing the usual homework.
Toll Brothers is a 'big builder' in my area. I live in SE PA. About 1/4 mile from me, they built 75 new homes starting at $450,000 on up. (That was 5 years ago.) I don't really think they've appreciated that much if at all. They're built on 1 acre parcels, and they look like they're WAY too close to each other especially when you drive by them. Yes, they're beautiful homes but I think they're over-priced. I guess if you have the kind of $$$ they want for their homes, they can charge like they do.
Have your brother talk to other builders and ask them why he should by from THEM and not from Toll Bros. Also, find a local small-time builder or 2 and ask them the same ?'s. Obviously, both types of builders have their 'interests' in mind when you have a problem.
I think if your brother has the $$$ to spend on a TB home, he has the $$$ to hire his OWN New Home Inspector. That's right. Read a recent thread where we went through all this: New Home Inspector - Also, he ought to get his OWN Real Estate Lawyer that's familiar with New Home Construction Contracts. In short, get people to help that are looking after HIS interests; NOT someone else's.
Personally, I'd hire the New Home Inspector. Visit ASHI.com for how to find a Home Inspector. Be sure to find one that has EXPERIENCE in New Home Construction! (DO ask about their 'experience'.) My best to you (and your brother.)