Horrible. DON'T let them to build your home! At first we thought it was just us but later found out that all of our neighbors were having the exact same problems. They do not return phone calls. They will try to get out of fixing even the most obvious of mistakes in your new home. If they say it will be ready by a certain time - you can count on it being at least one year later than that. We (and everyone we've talked to) has been through nightmare after nightmare with the owner of Shamrock (Dan O'Neil) and has had to threaten legal action in order to get anything accomplished through them. I don't know how they are still in business!
Pros: nice person answers the phone
Cons: everything, will not respond to requests, will try to get over on you, mean, etc.