Most topes are good fun if you get off the seat a bit and your suspension is set correctly: each wheel rises and falls independently, the bike bucks twice without lurching, and you get to pass all the soot-belching buses and trucks which slow to near standstill at each tope.
Miss one in the shadows or neglect to come high enough off the seat and bad things are possible. Non-typical topes can also do you in--around here they're sometimes installed in a series which is specifically aimed at motorbike wheelbases, so that back wheels drop precipitously while front wheels are launched skyward, but cheaper variations (like the ones with a broad, flat top combined with steep entry and exit) are just as dangerous. Plus every so often I've found one which is actually taller than my bike's clearance, and the third bounce when the whole bike rebounds off my skid plate really messes with my timing.
But 99% of the time they're a boon to motorcyclists--fun, and a competitive advantage over other traffic. What's to complain?