It took a bit of effort to find the profile for Pronabolin, which is always off-putting for me; IMO, you always want to be able to see the supplement facts on the product's site. With that said, I was able to find what appears to be the supplement facts elsewhere:
Let's look at it now:
Regarding the foskolin, it has 125mg of an unknown extract (it doesn't even mention extract, so it could just be ground powder). Compare that to AlphaMax XT, which has 25mg of 95% forskolin extract per serving (or 50mg per day), which is consistent with the effective dose used in studies.
Pronabolin also contains 100mg of a 100:1 tongkat ali extract, with no further mention of standardization, where AlphaMax XT contains 150mg (or 300mg/day) of a 200:1 extract that is also standardized for 2% eurycomanone, which is important, as often times a just ratio extract is rather vague and doesn't always tell you all that much.
Regarding tribulus, multiple studies show that it does not enhance body composition or exercise performance in resistance trained males:
https://www.ncbi.nlm.nih.gov/pubmed/10861339
https://www.ncbi.nlm.nih.gov/pubmed/17530942
or testosterone:
https://www.ncbi.nlm.nih.gov/pubmed/15994038
Regarding fenugreek, one study that noted benefits in strength and body composition used 500mg (standardized for 70% trigimannose):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2978122/
Other studies are mixed in results, and tend to use 600mg/day Testofen (which may be what's used in Pronabolin), where Pronabolin only has 300mg/serving, and 30 servings per bottle, so at normal dosing (1 bottle ~ 1 month), you're only getting 1/2 of the studied dose.
Also, it seems to be insanely expensive, at $79.95 for a 30 day supply from their website.
You're much better off with something like AlphaMax XT than Pronabolin IMO. There are many quality test boosters that are better than Pronabolin, and much more affordable as well.