I don't know that I recommend it, really, but it's the last time you'll be able to do it, so it's a useful thing to know if you're planning on delegating a large percentage of your SP anyway.
It's pretty hard to drain your VP all the way. I usually just try to vote down to 70% or so.
Got it. Thanks for the clarification. I am usually at 50-60% after I upvote my friends at 100%, so this will be useful for me. I will save up to 90% then go vote crazy one last time. Thanks.