Looking for an AR in .243. Who makes these?

I am looking at Armalite because they are the only manufacturer I know of beside DPMS which I am not interested in.

Who else makes them? Which do you suggest based on personal experience.

Any reasons not to go with the .243? I chose this because I like the versatility of the .243. Wanting something with a little more energy than the .223 but not so expensive and loud as a .308.

I found a .243 upper. Is building an AR 10 lower much different than building an AR 15?

Thanks.


Montana MOFO