Disc brakes for touring bike

I have a dilemma for a long time: disc brakes vs V-brakes?

My curious part wants to try out the discs, but they are quite costly, so the greedy part tells me to find reasons to keep the money.

My reasons for thinking about them:

* In Northern Germany it drizzles a lot and rims get quite wet. There are few weeks when roads are covered with the snow or ice and temperatures are below zero. Given the fact I am over 100 kilos heavy with V-brakes I sometimes need to plan stopping.

* Doing rare trail riding I have to grip front brake lever much in order to maintain very low speed, my palm hurts sometimes after a long descent.

I found an excellent post by the lazy randonneuer, which gives a lot of info on that topic.

After reading it my conclusion is:

* It's good to have discs if you do really a lot of trail riding, if you commute in wet winter conditions
* It's not that good to have discs on a tour if you are flying, if you are riding not that much in wet area and without very lengthy downhills