For removal, I run either the ms 150 or the ms201T, usually until I run out of gas when comming in the bigger wood. Then I take the ms462. Sure, in theory you can cut relatively easily 2x the bar's size, but pratically aloft, it's a pain in the ass. A small bump on the bark, a small missmatch of the cuts, a 3 limbs fork and you are stuck. Same if you can't walk around the trunk, like with an heavy leaner or an oddly shaped one.
Even bucking on the ground with a "half" bar sucks. 1,5x is more rational for a dayly use. The 201T can do it no problem even in hard wood but that takes time. Be patient here.
Much easier to bring out the bigger saw, quick and effective. It's heavier but less tiring if you put the time in count. I climb with the ms661 too if I have to, even the 3120xp-44"bar, heavy and hard to move around but sooo usefull when comes some big ass poplar or willow.
An important point for the big saw in the tree : the bar length. 20" is my favorite. It can cut some pretty big wood but it's still user friendly. I mean, often you have to pull the saw out of the cut while bucking on spikes. 20" is the right length for me to slide out one handed the saw until freeing the bar tip while holding the log with the other hand/arm. 24" began to be too long and the bar tip barely escape. The 44", I cry and call my Mummy.