With a price tag of £69.99/$79.99 and a piece count of 807 it means you’re paying roughly 8-9p/9-10cents per piece, which isn’t too bad when you look at it that way. This set is also quite unique in that it contains the spoilerific Giant Man brick built figure. Also in the set is the airport control tower, a baggage car and a smaller version of the Quinjet.
Bag 4 finishes the fuselage and all that is left are the engines and tail section.  You'll notice that this aircraft has a bathroom on board as well as some storage for a non-existent flight attendant.  I think this is the first time that LEGO has put some additional details into aircraft besides just seats.  Also there is only one pilot for a 2 seat cockpit in the set.  
Even in terms of play value it mostly seems to be a trade-off — 60104 loses the vending machine, cafe, baggage x-ray scanner, and a few seats on the plane but gains a baggage conveyor, a restroom, a refueling tank for the plane, an additional minifigure, and more seats in the waiting area. It's pretty nice to see the value of a LEGO air terminal remain fairly stable even though the price has not increased.
Basically, the only thing that the two sets have in common is that they both have planes. However there is quite a bit of difference on the inside of the planes. There are a lot more details in the Friends plane. In addition to the seats, there is a rolling service cart complete with refreshments, emergency lighting as well as a larger galley and lav in the back of the plane.
Agent 13 has a pretty plain appearance, with caramel-coloured wavy hair, and a black, spy-like top. Her torso has some nice details, with sharp, angular lines that all combine to form a rough outline of an upside down star. She has plain sand blue pants and rocks a sub-machine gun accessory. I like regular LEGO firearms, so it’s very nice to get one in this set as they’re fairly uncommon.