Good solid housing from Aquatica and the second one I've owned. The machining is excellent and all controls worked first time! They've improved the coating as mine is showing very little wear even though its been on around 500 dives and spent two months on the end of a pole last year. I did have a probem with the flash connector and have since lengthened it slightly but this is a minor problem. There is a small amount of corrosion around the top catch but then again not much. Considering what its been through so far it has coped well and I wouldn't have any hesitation buying the D4 version perhaps in the future!