CyberLip is about as good as a decent Neo-Geo beat-em-up. Generally, they are fine games but when compared to the games that inspired them, they fall short. That said, it also isn't a "bad" game and the difficulty is actually pretty balanced for an early Neo arcade release - especially a run-n-gun.
It moves at a brisk pace, has lush graphics, tons of hilarious voice samples, and I enjoy the setting and "early Neo" feel it has. There are two things that hold the mechanics back - the inability to shoot down while jumping, and being able to aim and shoot up while walking. Because it's a Contra clone it's impossible not to compare it to Contra 1 and Super Contra, but it would be unfair to compare it to Metal Slug. Once you wrap your head around "it's not Contra", then you'll have a good time with it. A worthy part of the early Neo library, for sure!