The fact that it's almost arcade perfect with 2 player co-op makes this game hard to leave on the shelf.
There are reasons for this, mainly that the port was near perfect, the game itself was very good and the controls were some of the best on NES. So basically, it would be very hard to be disappointed by this game. So the visuals and speed of the game are very good. The animation feels very smooth and solid. Bubble Bobble has no slowdown or frame-rate drops from when I've been playing so far, which is all good.
That's not the end of it though, the sound is excellent. Although there is just one track throughout the vast majority of the game, it isn't disappointing at all with all the sound effects sounding crisp and intact. And lastly the gameplay is just perfect. Bubble Bobble has the right mix of puzzle, strategy and platforming to be one of the most playable games on NES. Since Bubble Bobble applies to so many genres, it's hard to dislike the contents of the gameplay features, for anyone.
Combined with levels, beyond levels, this truly is the real deal. With 2 players, that's right, 2 players, coming back for more and more. So this has replay value worthy of kings. So what exactly stops Bubble Bobble being the best of the bunch on NES? Well, the gameplay feels way too slow. While the frame-rate itself is speedy, it seems the game has been set in slow-motion, perhaps for the less experienced players. This really takes a toll on the gameplay.
Also, the sound can eventually get annoying, with that one song almost being embedded into your head because it has been played so damn much! And lastly, even with a password system, this game really requires something else to continue where the gamer left off, especially since some levels grow harder and harder as you progress throughout the game. Although even with it's masses of levels, it's quite short.
In the end however, Bubble Bubble is an excellent NES title, worthy of your attention, no matter what type of gamer you are. It's a shame the game was released more later into it's life because it never got the attention it deserves. Take it from me though, you will indeed enjoy playing this game and the fact that it's almost arcade perfect with 2 player co-op makes this game hard to leave on the shelf.