I tried ripping with a peg and raker and the M tooth saws. A crosscut saw would not normally be used to rip saw with. If you hit a knot (embedded limb) you will be ripping, no matter if you want to or not. I did a little test on alder that is a soft wood and both saws did cut some. The Simonds 520 I used cut nearly five times faster then the M tooth. The M tooth cut very poorly and I'm thinking that a hard knot at the correct orientation could stop all progress on the M tooth.

The M tooth does not really cut on the bottom of the kerf like a chainsaw or like the rakers of on a peg and raker. It makes sense that it would not rip very well.