as some who used both weapons on the range. The FN C1A1 was a nice piece of kit, it had the range for long distance shots, it looked like a rifle , the wood and metal parts all oiled it look very nice on parade. it was a better weapon to drill with. nothing wrong with it that way.
C7 family came into service after my second year in the forces, and I was not at all impressed with till i got the chance to fire it. It did seem to feel lighter in training and field use. I shot just as well with it as i did with the FN family.
but the whole thing comes to down the age of the weapons in questions. my FN was made in the 1950s, I am thinking 1953, it was almost 40 years old when i got it. how much longer of a life would the weapon system have. with the use and abuse svc weapons get how long do they last without serious upgrades, replacement parts. Costs and the fact that 5.56 was the NATO ammo standard for small arms.
Ask any old soldier the first weapon he shot or was trained on was the best.
For todays combat and requirements I would take the C7 family over the C1 because I could carry more ammo, have better sights, have more fire power within the section. most of all the resupply of ammo is far easier since most countries in the operational areas use 5.56 , hate to run short and have to wait for it come in from Canada.
just my thoughts, donning flame proof shorts now