I posted on here late last year with a wanted ad for an E53 X5, didn't manage to find a car that ticked all the boxes and then was offered an E46 M3 at dealer p/ex price so couldn't resist! Drove that through the winter and have just sold it on and money is back in the bank

Returning to the for sale ads I was looking at the price differential between the E53 and E70 which is slowly closing and with money in hand I am starting to wonder whether a 115k E70 might be a better buy than a 90k E53 - but this might be man maths so looking for some advice.
The car will be used for family trips, days out, holiday, mountain biking, visiting family up and down the country so general family duties but in a year will probably be lucky if it covers more than 6/7k. With that in mind the higher mileage examples aren't such an issue for me as in effect the mileage will average out with my minimal use.
So can anyone that has gone from an E53 to an E70 give me some opinions and advice on which might be the better buy. The market for the E53 still appears to be strong given its age now so wondering if they will just slowly depreciate from here on in??
How different is the ownership prospect of the E53 and E70??
Any info would be most welcome.
Si