Something that you really want to think about is how you are going to feel when you drop that brand new VStrom the first time. You see it laying there with broken bits hanging off, maybe a big dent in the tank, bent bars, bent wheel, etc. Plus then you calculate that you lost 20% value when you rode it away from the dealership, and now with the added damage, it has gone down some more. Is it really a good idea to learn on a brand new oversized bike?
As many have said, get a smaller bike to learn off roading on. There is a reason that smaller bikes were made. To bash up and learn on. Once you have learned all you want to know about how to fall off and pick it up, then you can pass it along to the next new person that wants to try off roading.
Also, remember that in the off road world, bigger is not always better. I have seen 6 foot guys having a grand time on little 250-350cc bikes. They can go places that the bigger bikes can't, mainly due to being lighter and more agile. Some riding skill helps as well. lol.