Love the PC in the 141.
One thing that has been mentioned before which may attribute to why I like it so much... that pc likes track speed. You'll find that an M7 with a 162 won't be all that impressed, but the shorter you go the easier it is to spin & the more it shines. I've said it before, the 141 we have will go places in up to 2' of pow that a comparable 153 will go, I think some of that is just due to the fact that it runs 5-10 mph higher track speed. In 2.5+ though, the longer track starts to shine & in 4+ I get my arse handed to me. Weekend before last I rode 4+ feet with a very soft base & got stuck more times than I ever have before in one day (so did nearly everyone else) & I see that when there's nothing to grab onto under a few feet of snow, the short track struggles.
In most conditions though, it's great.
btw, what bearcat said about reflexes is very true. The 141 will outmaneuver a longer track, but it also has a downside, as it can go from going the right direction to going the wrong direction in a hurry. On the M5 I'm not sure that you'll have the skis in the air like my 141 does, so maybe not as noticeable without the power to stand the sled up so much.
You need to give her the long track & put that 141 on your sled... it'll make you a better rider!!!!