I work for a national housebuilder so hopefully might be of use. David Wilson is basically Barratt homes, as they bought them out a number of years ago, they use the name though on more high end developments as people perceive David Wilson homes as better than Barratts. However they are built from same offices and use same trades/specs etc. So if there is barratt development nearby with same house types there is a chance they will be up for less money. Persimmon do this with the Charles church brand. ( sometimes even the lesser brand has higher spec and for less money, so worth checking)
In so far as materials and trades, pretty much all the national house builders use the same subcontractors and suppliers, as like anything, mass housing estates are built to a price and built by hand. Mass housing estates have always been built in this way, even Victorian terraces etc were at the most part thrown up. Unless your going beskpoke detached house, estate houses from almost periods all have their benefits/drawbacks.
With modern estates, the main issues I would say in the south of the country are narrow roads, parking allowance for two cars on houses, but no where for visitors. No front gardens, very small rear gardens. Typical two bed houses tend to have French doors in the lounge to the garden, some people like this, some dislike as if you have kids or dog they tend to bring mud straight into the lounge. All houses tend to have en-suites, even in the small 2beds, which tends to mean the master bedroom can be smaller than the 2nd bedroom. Fitting and fixtures are contractor grade, they are fine, but like previous poster said with the doors, they are what they are. Windows tend to have a tendency to be on the small side, so some rooms seem dark. Some of the major benefits, up to latest spec with insulation and heating ( loft normally nearly half full of insulation nowadays!) so reduced energy bills, wide doors, hallways, stairs, large downstairs wc’s etc. Great for access and requirements for wheelchairs. The major benefit of all new plumbing and electrics and boilers, no need to worry about needing to get it changed. Most companies give you 2 years warrenties, then you get a structural 10 year warranty, worth research which company has good customer care feedback, some are terrible. Use the housebuilder 5 star rating to give you a guide, builders with less than 4 star I would stay away from. In all if you want to pay a little more than a second hand home, but want the none hassle of having to replace items, getting builders in etc, it’s the obvious easy option. Ps don’t bother paying for updgrades on carpet, carpets that get put in are cheap and won’t last, if they throw it in as an incentive then take it, but be prepared to change in a few years. Also don’t bother to pay for upgrades on appliances, you can get washing machines etc much cheaper from curry’s and fitted by them!