Not quite an XC70 but I have a XC90. I’ll start by saying I love this car.
I do Search and Rescue (myself and my dog) and I bought this to supplement my F250 (it goes through gas like a B-17 with flak holes in its wing), for going to training and searches. The XC90 has enough room for the 3rd row seating which the other SUV/Crossovers in this class (Tourareg, Cayenne, X5) did not. I figured that if I was going ‘large’ I might as well have that. Two side benefits of that is my dog’s 36” crate fits in back length wise without folding/moving the second row seats, and I can sleep with the second row down, with tons of room (6’4”).
A big plus is all the seats (including the front passenger seat) fold flat and flush, so you are never dealing with a hump or folded seat taking up room. I don't know if the XC70 is set-up the same way, but the XC90 has a rear mounted battery with space for a second 'house' battery, a very nice plus for camping.
That being said, maintenance on these will kill you if you can not do a lot of the work yourself. That is why the resale on any of the euro-lux SUV is next to nothing. I bought mine for 1/5 of it's ‘new’ price at only 6 years old. I have the V8 and it is the way to go IMO. It has crazy power (0-60 time is the same as my ex- Audi TT) but it gets unbelievable gas mileage. North of 20mpg (highway), and on many trips I’ve gotten better then 25mpg. I’d be the first one to call bull-******** on those numbers, but I’ve triple checked them.
While it handles great on the road (of course no TT there) and can really knock out the highway miles it lives for fire/logging roads. It has 8.9 inches of ground clearance (stock), and just eats those roads up at any speed (the faster the better….till a logging truck rounds the bend)
As you can tell I love the XC90, with the maintenance cost warning. That being said, it seems almost all of the newer cars regardless of the country of origin are getting crazy cost wise to maintain once out of warranty.