If you think you might eventually install a rudder using the Smart Track system, you'll find the mounting hole separation is 14 1/2" on Smart Track footbraces. I found that the mounting holes on my Keepers footbraces are 14 5/8" apart, having just removed them from my West River 180. I do not know the mounting hole separation on the aluminum footbraces sold by CLC, tho the description by CLC says 14 1/2." This is not a heart breaker for me, as I'll just enlarge the edges of both holes to accommodate my new footbraces.
It could be a Keepers quality control issue or just plain incompatibility. Due to their all-plastic construction, Keepers aren't durable for long term paddling anyway--Keepers are not keepers.
I have found Sea Dog footbraces mounting holes are also 14 1/2" apart. I hope Keepers has adopted the 14 1/2" standard that seems to be the standard. If not, I hope that CLC will either make the discrepancy clear or just not offer them.