Frustrating, occasionally buggy
I really don't know how this game is intended to be 'fun'. On most levels, completion depends on you executing 3, or 4, dart throws PERFECTLY. You've got to toss a dart over a ledge and nail a bloon on the other side - and if you mess up, you've got to restart the entire round. Pull off 3 dart throws in a 4-dart level, mess up the last one, and you're starting the whole thing over again.
Bug-wise, there were numerous problems, mostly with the pink tack bloons (their 8 shots sometimes manage to miss bloons directly adjacent to them, for example), and one nasty problem with angled blocks where the blocks reflected the dart before the dart actually reached them. Both problems are apparent in level 47 (the tack bloon in the top-right corner will always miss the bloon directly to the left of it, and the angled blocks leading to the two lower bloon rooms reflect too early, causing the dart to strike the metal block).
Even worse, it's impossible to avoid a level that's hard/impossible. Please, allow players to skip levels - perhaps beating one level unlocks 2 new ones?
I can't say I overly enjoyed the previous Bloon games, but this one truly takes the cake. Levels are seemingly intended to frustrate the player and dart trajectories are difficult to anticipate and seem buggy near the monkey (in level 26, trying to hit the Bomb Bloon to the monkey's left side is near-impossible, despite the fact that it's RIGHT NEXT TO YOU).
In short, the only redeeming feature of Even More Bloons is the ability to cheat with unlimited darts. I heartily recommend that any people who want to bother with this game, enable the unlimited darts option. If you want to try completing the levels with the allotted number of darts, go ahead - but don't say I didn't warn you.