I buy most of my bow making tools from junk dealers or yard sales, so my antique draw knives are staight but not so sharp. Not that I wouldn't like one that was sharp, but I'm ussually not wanting to take the time to sharpen it when I am ready to use it!
...but I was in the fine hardwoods store one time and I ventured over to thier tools display. I found, (and secretly bought without proper budgetting approval! Don't tell Mrs.), a flexible draw knife. It's sharp as heck and kind of small, but that actual blade is flexible and the handles are straight out to the sides instead of curved back. It was with a bunch of tools used by wood carvers. I've yet to have a chance to try it out yet, but I intend to do so this weekend or at MOJAM next week. We'll see...