There are people here with much more hands on SwissTool experience than me, but I wouldn't bother getting the new heads if I was you.
The new heads look stronger, but most of the bulk was added to the base, which also means the jaws can't open as wide as the older models. To be honest, I slightly prefer the older ones.
There are extremely few reports of broken older SwissTool pliers, and the problem with plier head play doesn't seem to be corrected by the new plier heads. I really don't think you would be gaining anything by getting the new heads.
Remember, if you do encounter any problems at some point, Vic will likely just swap your old SwissTool for a new one free of charge. Why the rush?