I have, Jim, and didn't much like what I found. COPA flies Boeing 737-700 to Panama and 737-800 from there to the US. Per Seat Guru, the configuration in business class is like domestic 'first class', limited recline of 7½", with the seats in row three further limited by the bulkhead behind them (again per SeatGuru).

To Miami, $1518, to Orlando $1610, to LAX $1281, to JFK $1333 (vs. Regent at $1,499 including transfers). The flight Rio to Panama is 7hrs 13min, from there to MIA is 3 hours, 3:15 to MCO, and about 5 hrs to JFK and 6:50 to LAX. The layover in Panama from the 11:46 Rio departure is less than 3 hours in all cases. The other COPA departure is at 2:37 AM; NG! waah

It's an option, but personally we'll stick with the Regent business class offer. If we were headed for the west coast, I'd be tempted.