Because of the nature of this particular game, a calculation of the theoretical return is almost impossible. The "Bonus Round" makes even a process of estimating the symbol frequency useless. There are often other opportunities where the return is easier to calculate. Mainly, the
Video Poker Listings, which actually include the theoretical return right on the screen.
Like you, I'd love to know the breakeven point of Millionaires Club, although the variance would be frightening even then!