6speed 4motion gearboxes. How strong?

I've kind of asked this in another thread but thought a new post might get a more specific answer...

I have just bought a 2012 4motion 6speed Transporter. It has 58,000km on the clock. I very hesitantly bought this after an unhappy time with the previous T5 1.9 TD 5 speed which I still own. I have had all the issues, DMflwheel/clutch failure, Drive shaft and spigot shaft failure, power steering failure and still juddery, and recently a gearbox failure. The gearbox was found to have an apparently common problem where the input shaft bearing spins inside the housing and wrecks the housing. All this happened from about 130,000km.

I also have a 2.4D T4 with 380,000km on it that has NEVER been touched except for a water pump and normal servicing.

My concern is have I jumped into the fire from a comfy frying pan? Is this a trend with VW increasing performance but reducing longevity? Is the 4motion 6speed box stronger/better than the previous 5 speed?
I love these vans they drive so well, lots of room and good performance but the reliability is scaring me off.

Thoughts?