It isn't even a question,the 460 is definately stronger,but feels much heavier than the 440.By spec sheet,Stihl claims it's only a pound heavier but it feels like more than that by the end of the day.
Even though the 460 is stronger,the 440 will still do everything the 460 will,and with some mild tweaks inside the engine you can easily make the 440 stronger.If I absolutely need a bigger saw to make a felling cut,then I will break out the 395 or 660.Then usually I'll just make my felling cut and put the big saw back up again.
I wouldn't say the 440 is a better saw than the 460.I have both,and you can't help but fall in love with the 460.