Absolutely convincing!
Incredible! This could've been on the actual gameboy, you recreated the feel of it perfectly! And if anyone knows, it's me.. the guy who clocked 3 lifetimes' worth of hours into that little brick. Little details like making the space scenes mostly light in the background, instead of black (as they would've had to on the actual unit back in the day due to the motion blurry screen) makes it a completely awesome homage!
The game itself is awesome too! The music fits the style and I foresee many hours sunk in this spectacular retro title! Keep 'em coming!