Kingdom Const. Company References?

We got a quote for roof replacement that seems reasonable from Kingdom Construction Co. on Newkirk Ave. I am hoping someone has worked with them before and can give us a reference. Was there work good? Were you happy with them overall? Was there a problem afterwards and if so did they stand by their work? Any and all information is appreciated. Also any other references for a good and reasonable roofer appreciated as well. We are in Bed Stuy and want to get a second opinion/rate ofcourse. Thanks fellow brownstoners.