I can only say that we've had issues, but I don't interact with it on a regular basis, so I'd say it mostly works despite issues. Dependent on how it's implemented, of course. We've demoed other AP automation platforms like AvidXChange and have stayed on MineralTree.
Issues like:
Not successfully sending payments to the bank for a week after MineralTree updated a contingent API.(IP whitelisting by the bank, probably)
Having no apparent auto-match for Netsuite POs that lack shipping costs to bills that include shipping.