I took my Polar D into the store and compared to the Artic. In my opinion, the under suits are very similar material weight wise and overall bulkiness - to the extent I didn't bother trying it on. I'm in no way saying the Artics are bad - just too similar to my existing undersuit. They did have a Whites / Aqualung Thermal Fusion in stock, but only a Medium size. I'm going to get them to order in my size to see how it measures up. Its interesting that they have the grill built into the Thermal fusion on the chest area, and also on the upper arm in the dump value area. I'd have to be absolutely certain before I forked out the best part of £300 though. The Kwark looks interesting too, so I may make a trip up to Leeds to try one on. Is there a benefit to going for an all in one suit? Other than the obvious one, that it can't end up separating once the suit is on. Could an all in one not impede the ability to perform valve drills in the future?