I have a 2010 and totally love it. However, I tend to thump along with the walking foot, rather deliberately, so the speed controller hasn't been super important. Maybe the extra tensioner is important at higher speeds? Given what a lot of good machines cost, the $300 difference between the 2000 and 2010 seems rather small. You might be glad of the tensioner later, especially if you're more accomplished than me.
hugs,
charlotte