I have the SB-27. Nice. Does all kinds of magic...but wish I hadn't been sucked in by the marketing hype. You can do just as well with a cheap flash - like the Sunpack 383 or even better, the Vivitar 283. Both have adequate power and a manual setting that allows you to adjust the output to fractions (1, 1/2, 1/4, 1/8, 1/16) of the total.
Spend the money you save on film and a notebook.