I agree, Masa is just as fast as Alonso when he's 100%.
This year he's not the same. His race pace is there though, it's probably a tenth of Alonso, but it's close enough that Alonso has never been able to run him down and pass him.
I hope he's planning to kick Alonso's ass next year. Same like he did with kimi, lay low one year study the teammate and blow him away the following year.
I wont underestimate Alonso's attack power or his speed and car control though. Masa was kimi's equal, so we should consider that when we judge Alonso's performance agianst him.