I've had mine since March 2014 and done 10 thousand in it.
Fuel economy is ok, ish, 40 mpg for me, but a lot of that is short tripping in and out of Central London, same as the Mrs' 1.2 Lounge.
They do loosen up after 6 or 7 thousand (and it's fairly wise to do an oil change at 5) and start to do a bit better, but it's a hard car to plod along in, I enjoy the rip of the engine far too much to bother with mpg!
Not just leathering it, it quite good fun to chug it around in higher gears.
Try third where you'd normally use second and just let it burble away on the torque.
I find from cold, the change from first to second a bit rough, it soon warms up and smooths out though.
As already written, Eco is pretty pointless, it's just to con the emissions/tax rating, best for 50 mph cruises on motorway road works, though I find it ok when I pull a trailer along the motorway.
Long hauls I find it a bit uncomfortable, I recently raised the front of the seat up 6mm with a couple of spacers, this has helped a little.
After a few months my brakes started to honk a little, seems they built the calipers up dry, some owners have been back to the dealers and had new pads fitted, seems they are like all Fiat brake pads, a bit ****e!
I've had them get a bit gritty too after a bit of off road action, so a good jet wash is needed if it's been in the mud.
Off road grip is brill, I've had all sorts of 4x4s and mine often pulls a trailer in and out of farmers fields and tracks around Kent and Sussex, nothing matches it for grip due to it being so light, it doesn't sink in, it just dances across the surface.
On some of the smoother, gritty tracks it can be pushed a little and get some four wheeled drift on the bends, but my trailer usually ends up in a hedge!
Clearance is a bit of an issue for me, rutted tracks have it bottoming out quite easily and uncomfortably, also mine has the normal, low bumper and front splitter which buggers up approach angles, luckily it's all managed to bend (and bend back) ok so far, but I don't think I'll manage to keep it all attached for much longer.
I've suffered window blow outs, the bonded rear screen and one quarter light have just shattered on me, methinks there may have been a fault at manufacture, like a bubble, nic or chip and they've just shattered in front of my eyes.
Mine are the dark tinted windows, so might be just limited to those.
I just noticed a few stone chips to the bonnet, the paint doesn't look too thick and a bit of metal is showing which will need treatment sooner rather than later.
One thing I do have trouble with is it's magnetism!
Three times it's been hit parked outside the house.
Someone reversed in to the tailgate, creasing it and smashing the handle.
While I was waiting to repair that, someone smashed the mirror clean off.
Last week a scooter crashed in to it, luckily it was only a wheel arch trim and the scratches polished out.