My house is built by Claridge. Lousy builder. A lot of design problems causing headaches. E.g. ventilation, exhause pipe discharge. I will never buy a house built by Claridge.
It's not a fair race. Richcrafe sells over 3000 homes every year while Tartan sells only 500. If 10% buyers from Richcraft vote for Richcraft, Richcraft will get 300 votes. If 50% buyers from Tartan vote for Tartan, Tartan will get 250 votes. If you compare the votes not the percentage, then it's not a fair race.
If one had a good experience with one builder, then s/he will choose that builder again for the future home. Also, the word of mouth is another source of information.