I've used them - really good bunch, very good work, professional, and the video diagnosis/updates on work were bloody brilliant. Would certainly recommend them
For interest, the thread on my engine woes, complete with lots of videos from Redish and a nice happy ending is HERE: https://z4-forum.com/forum/viewtopic.php?p=1783906#p1783906
I've read good things about them but living where I do RBM Hampshire in Hook are just so much easier to get to, and Ross has had plenty of positive feedback on here.