My Mercedes Becker Sat Nav stopped working and I found Revtronic on the internet and called them to ask about repairing it - they were so helpful and friendly and talked me through what I needed to do, I sent my Sat Nav off on the Wednesday late afternoon and it was back to me fully repaired by the Friday morning!! Amazing - such a quick and hassle free service I can't recommend enough - thank you so much, excellent service and saved me over £150 which i was quoted for a new device!! more than pleased!