Weight, reliability and reassembly. You defintely appreciate the weight after carrying one or the other for 25 miles or so. That is even comparing with the last m-60's with the shortened bbl and forward pistol grip. Reliability, well that speaks for itself. Yes, you can "break" an m-60 by putting it back together wrong. The 240 is more idiot proof. I know they are always making better idiots so stand by to stand by.....