AR-15 vs Glock 22 & 1911 45acp?

I was going to make another gun purchase and i cant decide if i want a carbine ar15 or a 40s&w glock 22 w/ a 45acp RIA 1911. The Glock and the 1911 will cost about the same as the ar15 so im stuck as to which one(s) i should buy.