I disagree. The ms260 has an inboard clutch and feels light and trim. The MS261 is much larger dimension wise and weighs more, that's why it feels the way it does.Hot enough to melt bearing cages in short order, it seems - at least in the UK.
The inboard is part of what makes the saw feel bulky and clumsy to handle as well, in addition to the technical disadvantages.
I wpuld think those bearing failure are either because of material issues or operating conditions. IE too lean and not enough lubrication.