I just received an email from Popular Woodworking about this iGaging micro adjust wheel gauge. Looks like it's just released. No idea of the quality of the tool but iGaging makes decent tools, not top end tools but usable. The big advantage of this tool appears to be the price - $24.
Here's a link to the basic wheel gauge, and here's a link to wheel and mortise gauge.
I plan to order one of the wheel gauges to see what it's like. I teach hand cut dovetails and recommend to my students that they buy two marking gauges. If this is a decent product, it might be attractive to people starting out.
Just wanted to pass this info along.
Mike
WheelGaugeA.jpg