Great!
...until it becomes nearly impossible. The difficulty curve is all over the place in this, some of the levels being near impossible, even having watched the walkthrough. Not nearly as impossible as its sequel for sure, but having levels where you only have like a tenth-second interval in order to succeed the shot (and when you miss losing all your score) just makes it frustrating instead of fun.
Overall very fun, but with the difficulty stuff and score-loss stuff, I can't give it any better than a 7