I have both the Finch 1 and Finch 2. The Finch 1 is slimmer by about 1/16", smoother opening, and is saber-ground. The opening hole is larger, more positive, and has sharp but more radiused edges. The backspring is a little weaker and potentially the Finch 1 could open in your pocket. The screws are all Phillips.
The Finch 2 is FFG (my favorite), has a nicely strong backspring, is a little grittier opening, and has Torx screws. The opening hole is smaller and the edges are uncomfortably sharp, but still positive. Weight-wise I'd call 'em even because of the cutouts on the rear of the Finch 2 handle.
Hope this helps.