I'm a big fan of the Kabanosy in Marianski (with some garlic and cayenne tossed in), especially if you hang them for 2-3 weeks to dry a bit.
Natural always seem to turn out better for me. My last batch I did 1/2 sheep, 1/2 collagen and for some reason the collagen wanted to ooze fat while the sheep were perfect. Plus texturally the natural are nicer, sometimes the collagen seem to add an unnatural chewiness.
Pigs are magical creatures.... they turn vegetables into BACON!!