I've been runniing a Nissan X-Trail for nearly 4 years now and have been impressed with it.
On a longer run it will see nearly 50mpg (up to Inverness earlier in the month and it was between 49 and 50) and with general running about, commuting, stalking etc. I average around 40. Running costs are also good and a recent main dealer service on mine was about £130. It does fine off road though, clearly, will never be a hard core off roader but if you've a quad you've got that covered. I believe that decent AT tyres are now becoming more easily available for the 17 inch wheels. Mine runs on Yoko Geolander ATS all terrains. I believe they tow well, though I only ever have sheep in a trailer on the back, and are very popular with people who trail horses about a lot. The boot is impressive and with the seats down gives a flat load area that will easily carry my high seat, a stag in a big fish box and other stalking gear. There is a great system of shelves under the load area to keep all sorts of stuff handy and easy to access even when the boot is full. It is also very comfy, has all the gadgets and even after 4 years I really like it and just can't see what there is out there to replace it - if I had to change it I'd have another one.
On the down side access to the rear seats can be a bit tight and there isn't a pile of knee room in the back if the front seats are fully back and on a cold day mine sometimes turns over a few times before it fires up, though it always starts even in winter 2010 when we had daytime max temps between -10 and -15 for about a week.
I don't know if that meets your requirements - I wasn't dead keen on an X-Trail at first and nearly bought a Discovery 3 and on reflection I'm just so glad I didn't end up with a Discovery, the X-Trail does everything I need and goes everywhere I need to go and doesn't cost £500 a month to repair which means more money for stalking. Don't under any circumstances buy anything made by Land Rover, you've enough trouble in your life without paying for the privilege of having one of their problems sitting broken down in your driveway.