I have spent the majority of my career in the home building industry and have worked with two of the three builders that you are inquiring about. I consider myself very knowledgeable with the new home building process and the entire construction management process.
Due to my construction background, I would put great emphasis comparing actual construction materials and the construction process of each builder. They all use the same tradesmen, though there may be differences in best practices used.
So, the main questions/answers that I can help you work through is what construction materials are being used, how do these products perform/longevity and what QC measures are in place during the construction process to ensure a good quality home for you.
If I can be of help to you, please send me an email, firstname.lastname@example.org.
All the best in your home search.