I'm ordering this unit from Zietronix today:
I will couple it with this gauge:
The base wideband unit can take RPM and TPS (Throttle Position) inputs and be logged via a PC.
Optional inputs (using their sensors):
EGT (exhaust gas temp)
IAT or CLT (1 temp input - coolant or air for instance)
MAP: Manifold pressure
The pricing is reasonable and the gauge is pretty slick. The digital readout can be configured to toggle through AFR, EGT, IAT or MAP plus the outer ring has a scale on it that can display any of the above - so effectively, you can look at 2 values at the same time - one will be numeric and the second a LED dot that lights up next to the perimeter scale.
With the logging of RPM, MAP and TPS it should be easy to look at AFR values and be able to effectively tune the F and L maps a bit more accurately w/ TuneECU!
The only downside is it's not weather resistant. I'll give a full update once I get it in my hand and installed.