There are basically 2 types of caulks. The first type is solvent-based and they dry through evaporation which leads to shrinking and cracking. These caulks can be identified by looking at the ingredients which include the typical aromatic solvents.
The other group are reactive chemistries that cure through a chemical reaction. Silicone and Urethane are in this category. These generally perform way better that solvent-based products.
Sikaflex is the best in my opinion.
Too much to cover here. A good place for more info is the FAQ page at www.delamrepair.com