I've used both nitrate and butyrate dope for years and never noticed any significant difference in shrinkage or solids. The use and application is virtually the same for each type (there is more difference between brands than between type). Butyrate dope was developed as a replacement for nitrate dope for full scale aircraft because the dried nitrate film is highly flammable (similar to the old celluloid movie film). The dried butyrate film, while it will burn, has a much retarded flame rate compared to nitrate. A side effect of the new butyrate dope, of interest to modelers, is that while nitrate will soften in presence of glow fuel, butyrate is pretty glow fuel resistant. I didn't say fuel proof because on direct exposure, some butyrate will dull a little. It won't soften, however, and the dulled areas can usually be buffed out with an oily rag.

Of course the solvents used in both types are quite flammable so proper precautions must be taken when spraying and brushing dope of either kind.

I would definitely not use Stix-It to attach the Koverall. It works OK, but the fabric tends to fray a lot and makes a neat joint hard to do. A much better procedure is to use dope to attach it to the structure. The dope binds the fibers so that they may be trimmed with a razor blade without fraying and the edges can be blended with a little more dope on a finger. Also with the dope, there is no danger of the attachment softening with heat and pulling away when you shrink the covering. Though I have used dope for this a lot, lately I've been using a fabric cement made for full scale applications called Fab Tac. It has a faster tack time and is a little easier to use. With either produce, I use a hair color applicator bottle with a small tip to apply the material and smooth it down with my finger. A little acetone or thinner cleans up the fingers.

(A non-tautening version is available in both nitrate and butyrate where heat shrink covering is used and the shrinkage must be controlled.)