Caber is a bit more expensive as you've seen. Can be a bit elusive for some as well. Id opt for it if possible but usually Pramipexole is the much easier option to obtain. Efficacy of the compound, availability, and price being main factors in that order Imo.
As long as you keep your E2 in check with an AI, your prolactin levels wont be at such an advantage to be increased. Cant remember your intended Deca or Tren dosage off hand but if it was going to be higher, it would be more effective using a secondary but more direct route in a prolactin antagonizer to help guard against the effects. Caber is also known to illicit increased libido as a positive side affect for many.
Same goes for progesterone. Although getting it wrong with progesterone can be a bit more detrimental as gyno is a result if those along with E2 levels are too high. As we should remember, its progesterone that causes gyno, not prolactin. Using an SPRM (Selective Progesterone Receptor Modulator) like Asoprisnil here would work best, but it is only recommended in extreme cases as it can easily tank levels causing secondary issues. An AI like Aromasin over Adex would prove best here in defense against any 19-Nor due to its effectiveness over progestins.
You're very welcome Fullback40. I'm glad I can help spread the knowledge I've come to learn about this wonderful world of AAS