Excellent experience with Solarcrest - good timely responses, competitive prices, provided basic design drawings and very helpful all the way through (as I used my own local heating engineers to fit it - their first attempt!). Not many queries but Solarcrest were extremely helpful with telephone queries - mainly electrical - being sorted instantly. System was easy to install, balance and commission and it works well - I installed the Vent Axia Sentinel Kinematic Plus B systems in two newly built houses. Solarcrest even took back small amount of surplus materials for credit after completion. Overall very nice people to deal with and would not hesitate to recommend to anybody - novices with self builds or professionals alike.