The Swissport lounge Finnair is using at ORD was packed on last Friday. The passengers were mainly from other than Finnair flights. Even though there was basically no seating available the Dragons were happily accepting new guests. The food and drinks served are not good quality.
If you arrive early and based on your OW status are able to use either the BA C or F lounge I would recommend that. However the BA lounges close by the time they board the last BA flight departing at 8.35pm.
When I went to the BA F lounge the Dragon first declined access for me as a Finnair passenger. When I said that I have access as an OWE, the Dragon stated that the lounge was full. I did point out that it is half empty. Then she said that my flight is late and they will close soon (it was still open for +45min). After I said that I know that they will close the Dragon let me in.
Lounge is relatively small. The food servings was good quality and they serve a good selection of drinks including champagne.