Anyone using an Innovate LM-2 A/F ratio datalogger

They are pretty good. I'm using an LM1 plus Auxbox.
On the plus side - Innovate's WBO2 reading method responds very rapidly and accurately. You can recalibrate to free air as needed. My recollection is that the LM2 comes with the rpm converter built in. Having RPM is critical to make the decisions on carb tuning.

On the down side - it is a consumer grade product and not surprisingly there were some issues with the RPM readings, especially on the LM2. Hopefully they have by now fixed the issue. You can send in for repairs - customer service is slow and annoying in the US but they do respond with gentle prodding.

The system can be sensitive to ground offsets and electric noise from alternator. These can all be overcome if an issue and Innovate instructions cover this. The instructions in general are OK but not super great.

If you are interested in more than wide open throttle, it is helpful to have a setup which also can log manifold vacuum and/or throttle position. But that adds to the costs.

With their WBO2, the bung can be welded anywhere in the exhaust system. But on radical engines anything too close to the tailpipe will pick up outside air at low rpm. On the other extreme, in some situations an extended bung is needed.

Overall, it is probably a good choice for your situation.