^: yeah, for a lot of the later stages you need to catch on quick when stuff is going to spawn behind and make sure you play up a bit. For all the stages like that, that I can remember, you're safe if you rush to the middle as soon as you see things start to come up ... then just slide behind them and blast them down.
"It is not a disgrace to fail. Failing is one of the greatest arts in the world," however --
"Believe and act as if it is impossible to fail." ~ Charles Kettering