Both the Scout and the Scoutmaster really benefit from the addition of a motor controller. The VPI SDS is around 1000.00, and the Walker Precision Motor Controller http://www.walkeraudio.com around 1700.00 (with the Valid Points and Discs). Stable speed and ease of switching between 45 and 33 made a big difference in both the Scout and Scoutmaster in my system.
The upgrade to the JMW Signature arm is probably the way to go (700.00 with the trade of your stock arm). The differences between the two arms are not subtle. Be prepared to wait a bit for a Signature arm though. VPI seems to be a bit behind in meeting the demand. In addition, the 300.00 you'll have left over from the arm upgrade will make for nice seed money toward a motor controller.
The upgrade to the JMW Signature arm is probably the way to go (700.00 with the trade of your stock arm). The differences between the two arms are not subtle. Be prepared to wait a bit for a Signature arm though. VPI seems to be a bit behind in meeting the demand. In addition, the 300.00 you'll have left over from the arm upgrade will make for nice seed money toward a motor controller.