Bought a Barratt new build flat in 2007. I'm still living in it, so it can't have been that bad, although a few points worth noting:
(i) If doing it again I'd be inclined to instruct a quantity surveyor or similar to inspect the interiors to see where corners have been cut and where snagging issues arise. I thought I'd done a good job on this myself, but years later found annoying issues arising such as, for example, the TV aerial and telephone sockets in the master bedroom being connected to absolutely nothing - clearly corners were cut by the builders. That said, this place was put up in 2007 at a time when the housing rush was at its worst and flats were just being literally thrown up, so things may have improved since then.
(ii) negotiate, and negotiate hard. I was fortunate to be living at home at the time so could afford to walk out of their show room as often as I wished, and my flat was also the last one to be sold on the development so they were keen to get rid of it. For the sake of not being able to choose my kitchen and bathroom colours I happily saved up to £20k on the purchase price paid by some of my neighbours for exactly the same property.
(iii) you won't know who your neighbours are: probably less of an issue with houses than flats, but I only discovered after buying my flat that Barratt had sold about 30/40 properties to one individual who runs them as party flats and now tries to purchase any other properties that come on the market. That means the two flats on the landing below me are both effectively AirBnBs, but to be fair these are more commonly let to families / workers than stag dos etc.