Considering entering the X5 world

[Matyb73]

Hi all,
I am new to the forum however i am a BMW man so i know i will be welcomed with open arms
I need some advice so i thought i would come to the guys in the know......I am an Aussie who currently drives a E60 530i M-Sport (which i love...and i mean love) and i am condering moving up the food chain into an X5. The reason I am condisering it is my hire purchase agreeement will be up mid year, i was considering rolling my current agreeement over for another year however luxury car prices are tumbling and interest rates are low so i am now in two minds. As the E60 is being replaced with the F10 in 2010 i would not want another E60 at this point as i dont like driving an old model, i keep my cars for at least three years due to high change over costs (government stamp duty etc) here in OZ. I am reasonably young (if you can call 35 young) with a wife and two little ones and if my wife has it her way (which she always does) another addition will not be far away.
So my dilema is what to do.....my wife has a Touareg so we have one beast of a car in the gargae already but should i make it two. There are no other sedans i would want, coupes are out as we need the flexibilty of having two four door cars. When i drive my wifes Treg i do like the high driving position and the presence on the road however i still much prefer driving the 5ER.
The only other cars i would consider are the Cayenne or the the RRS, the Cayenne is just a more refined version of the Treg which we already have and althought i am from an English background i am not sure about owning a RR....i have not heard good reports regarding their fit and finsih and their reliablity...and they do not hold there value well down under. No offence intended to anyone regarding these cars, these are just my uniformed observations.
So after that ramble if any one cares to comment or offer any advice it may help my decision making process.
Cheers!!!