Honestly, I think you are best off finding a dyno that has wideband O2 ability. To be accurate at WOT, you would have to purchase awideband set-up as standar types do not work under WOT conditions.
I think the cheapest wideband set-ups are in the $400 range, while a set of dyno runs with them checking with a wideband set-up costs about $75. Unless you make some hardware or software changes later, there isn't much need to continuously monitor.
I'm using something else because I didn't know better at the time but Zeitronix makes a really nice/versatile unit that people seem to be happy with. Also has EGT ability and extra data channels for logging boost and rpm at a pretty reasonable price, $279.00 USD. Zeitronix Wideband
To me it seems pretty silly to not watch your Wband o2, compared to potential problems, esp. when it's such an easy thing to do
thought it was a damn fine price till i saw the display, egt and map sensor etc were extras
although the waiting times were shocking the AEM proved popular over here @ about 300 odd quid, but it was a 52mm gauge with built in controller so a nice neat installation