Thanks all for your comments,
Here's a little more of the story and some of the reasons we tentatively called it a Dark Pewee as well as some of the doubts we had.
We were bothered by the wingbars (as also mentioned above) and felt the overall color was lighter than expected (from our fieldguide). Watching it, it was feeding much higher (about 30 feet) than we have usually seen Tropicals feeding (which tend to be down around 5 to 10 feet). It also returned fairly consistently to its perch during the 20 minutes we watched it. This is normal for Dark but not so common for Tropical. On landing it would vibrate its tail almost every time, but this is consistent for both. It also appeared to be larger than the Tropical Pewee, but of course size on a lone bird always has some risk, though we were fairly close to it.
The other question that came up later was when we checked distribution, the Dark Pewee is resident in this area (Caribbean flank of Cordillera Central) and is normally between 4,000 to 7,000 feet elevation. The Lodge is at about 4,600 feet elevation so is well within this range. The Tropical Pewee is common in the Caribbean lowlands and doesn't appear to get up to this higher elevation until around Cartago (seen at 4300 ft) and then up to 5,000 feet near the Panama border.
I know the Tropical Pewee is on the site list for the Bosque de Paz but I don't know how frequently the Tropical has been seen there. (I will email this question to them).
In any case, I didn't feel this was a "perfect" Dark Pewee and was interested in other comments. I know we don't have a photo in the BF database, and was hesitant to add this one since it didn't look like a positive ID.
Thanks again,