-- Last Updated: Jul-02-13 5:41 PM EST --
I have the 2009 Forester. In general I find the roof (as all the metal) to be very lightweight on the car that I am unsure I would ever go the foam blocks on the roof approach with the newer model of the Forester.
I initially had the factory crossbars and did have at least two 50-60 lbs kayaks on it with two J racks. It seems to hold alright but the real issue I had with it was the curve of the bars. It made it harder to position Js, bike racks, and cargo boxes on it due to the curve. I view their factory bar as being more for looks and the occasional load then a functional rack choice.
For base crossbars I prefer the Thule bars mainly as the square bars hold all kayak rack systems in place without twisting. If you ever go to place kayakers hang out -- lakes, kayak shows, etc -- you will see that any kayak rack on the round bars is twisting on the bar. Seems like some kayakers think this is ideal to have your rack twist down out of place but I view it as the grip wore out and you are one bump away from some roof damage. The round bars are great if you are attaching racks which secure to both bars, like bikes racks and cargo boxes, but with only a single attach point for kayak racks they will twist eventually.
I may have Thule cross bars but everything else I have is Yakima -- J, bike racks, and cargo boxes. Mainly because they offered locks on the Bowdowns and I had a good deal for a pack of locks. Both make great products overall.
I don't have a problem solo lifting at 60-70 lbs kayak over my head and then almost throwing it into the J rack. At 5'8" the J rack is bit higher than me on a Forester and I can just barely, with me on my toes and with a toss get it into the Js. Your height, ability to lift the weight and if you are going to have help are all going to matter. Js are the worse on a tall car and/or weak person. The stackers are bit easier assuming you have pretty short kayaks. The cradles and sliders are so much easier on a tall car or with a long kayak as you can just slide on from the back but you may not be able to get two kayaks on the roof that way.
Classic Freestanding Rack
Paddler's Truck Rack