I did exactly what you're doing now a couple of months ago after buying a car from ON and having it shipped here.
$270 from the dealer isn't terrible - most dealers charge around $200 and they're not Porsche. The benefit is that you have the people who know the car best doing the inspection, and can better alert you to problems that are idiosyncratic to your particular vehicle. When you've just had the thing shipped across the country, that's a benefit, because you may not have been able to fully inspect it before you bought it.
That said, the downside is that they're not necessarily particularly good at dealing with the inspection process. I had the dealer do my car, and had some issues with their methodology, leading to me having to actually call the government and get them to confirm the car should be passed. It was a hassle and they almost forced me to buy a factory exhaust system and put it in the car just so it could pass, before tearing it out and putting the aftermarket system right back in immediately afterwards.
Fortunately, I avoided that and things mostly ended up fine (including the car). However, I think at the end of the day,
I would suggest using Inspectacar. Inspections, including out of province, is what they do. They know the manual well and how to interpret it - in fact, one of the guys there (whose name escapes me) actually put me in touch with the relevant government people to solve my problem, even though I wasn't using them. Frankly, I owe those guys a beer or six. Plus you have the added bonus that they have absolutely no incentive to jerk you around or try to get you to pay for unnecessary repairs.
So that would be my recommendation, having just done what you're doing.
http://inspectacar.ca/