Macro: close up filters or extension tubes?

I would strongly suggest going with a decent close up filter first. Pentax extension tubes with all contacts and the aperture levers are a chore to find, which means you may end up having to stop down when focusing. Close up filters avoids this problem.

There's a lot of snobbery against using these but I've seen web-sized image results from these that are prettymuch spot on. Unless of course you blow your work up and make 10 foot prints out of them. Like so many of us really do.