I have just had a quick look at the Motability site, it shows the 2WD being a little better on fuel and a couple of hundred pound cheaper. Personally I not sure about the 4WD, but hat is down to choice.
Regarding the CVT transmission, Renault originally fitted this 2 litre engine and transmission to the X-Trail, but due to poor sales dropped the CVT transmission, I believe the X-Trail replaced this engine with the new 1.7 and no longer uses this engine. I get the impression Renault Koleos is using up all the old powertrain technology, but I am looking at it as an engineering. There is an art to driving a CVT transmission, it does not suit lead foot driving, if you are a careful driver and press then lift on slightly you will get the best of the CVT transmission.
Have fun with your new car
Unfortunately I have suffered a brain injury and occasionally I get confused and often say the wrong thing.