The house edge for Spanish 21 is generally better than the house edge in blackjack. If you ignore the effect of those jackpot hands, which come up as rarely as you might expect, the house edge for Spanish 21 is about 0.4%. This assumes, of course, that you're playing with perfect basic strategy. It's probly not worth your time as a card counter. However as a gambler, keeping a very simple count can at least lower the 3%~ house edge on the bet. Any game you chose will have their + and - but which one do you enjoy the most and will want to continue playing for years to come. I will say that 98% of the threads/ forms you reach out to for "counting cards" will fall in the blackjack section. That should tell you something.

-Dr.