It's not a matter of what Sonar or Cubase or Studio One can do. It's been a long time since the Pro Tools guys have abandoned their misconceptions. And if one contracts gigs on his own and brings his rig and all, then, sure Sonar or anything works.
But if Avatar studios or anyone of those guys call you for an internship tomorrow, being proficient w/ Sonar doesn't mean a thing, no matter how much "better" one finds it . They need Pro Tools guys.
We were discussing with a studio owner recently and he was telling us that he had a tough time finding a guy who could not only use Pro Tools, but the hardware that runs with it and all (not to mention mic a drum kit). Set-up a session and work according to certain standards - so when the mix engineer gets involved, no time is wasted trying to figure out what's where and re-organizing everything.
Dozens of kids came to him boasting that they could "mix music" but they had no clue how to work in a context where other people were involved, and where the opportunity that they are presented might have nothing to do with mixing. Unless you're dead set on being an independent, learning Pro Tools remains a must.