In my WS Zephyr 155 I was having issues getting the setting "just right" with the back band system. The factory phase 3 system is very good but the back band had a a way of slipping down unless very tight. I replaced it with a IR lounge band and instant comfort. The band still allows for full rotation and laying back flat but will not slip down. very easy to install after watching the internet video. The fittings and webbing are superior to the factory back band and seem to be of top notch quality.
If you are looking for a seat that feels like a rec boat lounge chair this is not your product. It is a very comfortable well built product. The only reason I did not score it higher is that for some people it may ride a little high and could interfere with a low fitting PFD.