As with any new technology I too was a tad afraid to make the leap. You never know... maybe all of a sudden on the second year after they're introduced, all the drives will start to fail suddenly without warning (think the IBM Deskstar 75GXP)*. But apparently perpendicular technology drives seem to be doing well so far. They at least seem to be lasting their warranty period so far. Aren't most drives today perpendicular anyway? (just saying you don't have the choice anymore)
* Check this out for a deathstar failure. It'll make your balls shrivel.
http://www.astro.ufl.edu/~ken/crash/index.html