Hi Hal,
The new driver is a whole new platform from the ground up. Different parts, different software, etc. With the WWD, the only time I've ever heard of stalls has been on pumps in which there was actually something wrong, which means the driver was doing its job. With the old driver there would be false stalls, like what you've described.
There are other benefits to the upgrade too, such as the two random modes, pulse mode for wave generation, feed mode, and the ability to wirelessly sync multiple pumps together. The WWD also runs about 5 watts more efficiently, bringing the pump down to about 28 watts at 3000 gph.
-Tim