No 60cc saw I have ever ran will compare to a 70cc saw, including my 562. Ported they get close, but still lack the torque, so your chain can't be aggressive and you have to feather the saw through the cut to get them near a good 70cc saw. If you cut softwood you may not notice as big of a difference in torque. Now saws like the 365 and 6400 have the torque as they have the same bottom end as their big bore brothers, so they really don't count IMHO, as they aren't stand alone platforms.
Now if you're familiar with Ed heard aka EHP he was throwing out some wild videos of his ported 562 cutting only a tick or two behind a stock 395 in 30" Maple. What people don't know is just how good Ed's chains are and how well he can operate a saw and make it look. There is more to it than power alone, especially if you're good.