I'm not crazy about either game. Lots of people like Card Whiz/ Royal Flush. It's a shooter's game, you're very involved with the drop targets but not much action elsewhere. Only 1 pop bumper located a mere 2-3 inches from the top shooting arch, far away from the game's actual objective. It's no surprise they all clean up wonderfully. Not a fan of this type of bonus collection either, it always felt like, "All or nothing," to me, kind of like Joker Poker.
The middle of the playfield on "Top Card" just feels a little too open for me without having some rebounding rubber incorporated to utilize a 3-pop-bumper configuration. I know there's a pair of upper kickers but their use is limited with that lower pop in the way.
I also can't stand the inlanes on this one. With a little practice, you can actually learn to goose a special inlane with a direct shot from the opposite side flipper. Without the standard 2-part wireform return lane that Gottlieb used on most, (with that harsh angle the ball turned on it's way to the flipper), Top Card's inlane rollover is reachable since the angle the ball needs to turn is compromised. It also uses a plastic as a lane guide, buffering any shot imperfection without losing momentum to actually reach the rollover. You may lose the ball down the side this way on occasion but that price for a replay obviously is worth it. It's no wonder Tim Arnold feels this is his "Detroit" Game.
My choice rather than Royal Flush/Card Whiz, would be Sky Jump. It appears to offer the same drop target set-up, but with 3 pop bumpers yielding much more secondary action. Instead of bonus, the drops present the game's road to "Specialville" for a chance at multiple non-score replays. Of course it's a single-player with no head-to-head capability so for that reason alone, may be your choice. Card Whiz does have a following, just doesn't do it for me.