Personally I use Swissol. I have tried Zymol and although it's very good Swissol is just as good if not better, and its so much easier to work with.
As you have probably experienced, with Zymol you really need to do the car as they suggest - a 2' by 2' area at a time. Leave the HD cleanse or wax an too long and its a real **** to get off. With Swissol you can cleaner fluid (equivalent of HD cleanse) the whole car in one go then buff it off, then the same with the Wax and its still easier than removing Zymol.
In terms of shine and protection, they are both very similar, although the Shield wax will probably last a little longer than than most others due to the PTFE content.
I have tried shield and it is good, however I wax the car regularly so didn't see the need for PTFE, and I wanted a higher Carnauba content so I went for Concourso instead.
