All fillers will shrink unfortunately. Epoxy has the lowest shrinkage (so low in fact you can generally ignore it). I've only used epoxy putties from Milliput, and these tend to be rather stiff, and hard to sand, and thus ill suited to covering large areas and parts of a job that require feathering etc. They are totally waterproof however and tough as old boots once set.
Polyester filler shrinkage is much higher, how much this affects your job depends on how thick you plaster it on. My own experience with this stuff, is that works well for most jobs, but you need to let it sit for a few days before giving a final skim, to allow it to fully cure. Even then, don't be surprised if you find that you get a bit of shrinkage over the following months.
One part stoppers are really only designed for pin holes and scratches. I use acrylic putty (3M Acryl red) which is great, and low in shrinkage, but I wouldn't use it to cover anything thick.