If you're working with electronics, you don't need all tools to lock, or you won't be doing lots of screwdriving, go for the Wave. If you're working with, say, plumbing, you need all tools to lock, or you will be doing lots of screwdriving, go for the SwissTool.
I love both the Wave and the SwissTool, but I've seen the Wave give slightly on occassion, as in bend. The SwissTool is solid and robust enough to be (ab)used as a hammer if need be.
The pliers offered by, say, the SwissChamp are to be used in a pinch, for minor repairs or adjustments, kind of like the pliers function of the Swiss-Tech MicroPlus.