I have been trying out one of the SEO VAs for over a week now. All in all I'm satisfied with the service although the VA was almost always late. Nonetheless he completed the tasks I gave him and sent reports accordingly. I'm mainly letting him do SEnuke blasts right now. He was sick one day, but Jake got a replacement who did his job on that day very fast. Also Jake has set the work times of the VA to match my timezone. There are only a few tasks the VA can do when you hire him. You have to be clear that you have to teach him what to do, give him training material etc. and answer his questions. You are not getting an SEO expert whom you can say "get my page to #1" or anything like that.
As I expected, the computers of the VAs are not that good, so they can't run a lot of things simultaneuosly and the internet connection as well as the power lines are having problems at the moment, but this could be due to the rainy season in the philippines (I also got a mail that two big tropical storms hit the region and affected the power and internet lines). And the access to the different blog networks and SEnuke is a huge advantage.