I feel sorry for people with a low-end pc that tries to run that kind of map. lol ( I know it's been made before the SB Load was implemented, but come on, if you can't expect it to be THAT high, you're blind. )
I think not being able to delete a SB is really stupid. I've got a good pc now that basically doesn't lag not even with Bakaru's or Sterrum's stuff. Not even with kiai on those. But when I had a crappy pc, even a simple SB'd map like http://osu.ppy.sh/s/14690 made me lag. I don't care about the score ( hence why I'm, like, #15k lol ), but not being able to enjoy one of your favourite songs just because of the SB is something everyone doesn't want. I'm sure of it.
SBs are good, distracting, funny, you have a nice time with it. But that's ONLY when you can reproduce those. If you lag with it, and starts to miss with it, it's something really annoying.
Maybe trying to ask for something perfect is impossible, but come on. If people can't play some good map just because of lag, this game will be pointless.