The G-Claron is an f/9 plasmat process lens. It has more coverage than the Commercial Ektar. It is also single coated. According to Schneider, the G-Claron needs to be used at f/22 or smaller at longer distances. I'd probably choose the G-Claron for the coverage, because it will use standard filters, and has a smaller modern shutter. The 210 G-Claron is mounted in a Copal 1 (if it is in a shutter) and the 8-1/4 Commercial Ektar is in an Ilex 3 IIRC.