I went the long route last year on a batch (6months) fermented with White Labs Berliner Wiesse blend and it was only mildly sour and pretty Bretty. I am inclined to try the sour mash approach this year (toss some whole uncrushed acidulated malt into the mash and keep it warm for a few days before pulling the wort off to short boil and ferment with a German ale yeast). It sounds easier, but will lack the leathery/horse blanket of the Brett.
This is how I am going to make my next berliner weiss. I might keep my smaller mash tun just for that. For anyone that has gone this route how many days would you keep the mash going? What temp range? Just add the german ale yeast, no lacto? Would adding lacto add anything else or is all the lacto you need in the wort?