I use keitech paddle tail swimbaits all the time while fishing, but I have not been able to find a definitive answer on the difference between solid and hollow body swimbaits. Do they swim / wobble / track differently?

Solid body baits are going to be more dense, so you're going to get a different sink rate from similar sized baits. IMO, solid body baits are easier to rig because you have more plastic to work with and there's more rigging options. How they wobble is going to depend on the rigging and how soft the plastic is. 

For me, if I am going to use a jig head and want a slow fall I will use a hollow body. If I want to get it deep with a jig head I will use a solid body. If I want a subsurface I will use a solid body on a T rig with a 1/16 oz pegged weight.