I think Buells are probably the best at handling. That seems to be what Erik is gunning for. And I read an article online somewhere by one of the big-name magazines (can't remember which one), and the XB9R came in #1 on their "Top 50 Best Handling Bikes Ever" review.
Back to the Blasts, there's a guy on the Badweb forums named EZBlast that has modded the crap outta' his. If I'm not mistaken, he's hit around 110mph... it's up to like 80+HP, and on a single cylinder! I think the case may be the only stock piece of the engine left, though... he's obsessed. 
~SM