I dive with the MK25\S600 and I love that reg (a little disclaimer I don`t ice dive and I don`t dive under 40 degrees) but it breaths like a charm hose routing is great and if you ask me I would bye the reg again the only thing is if your diving real cold I would go with the MK 17 G250V the 17 is sealed and the G250v has a metal barrel helps with freezing