It is a difficult choice. I had the same decision in 2010.
the recommendation to get on an ride both is the best. By the one that makes you smile the most.
when i was looking, the dealer let me take a WeStrom for a good test ride...over 1hr up mountain twisties. I was satisfied with the bike. It had abs which is very important to me.
I then took a bmw F650GS twin on a similar ride. The BMW is lighter, a bit faster and handles the twisties a bit better.
while i do a lot of dirt roads I do not really go off road, I believe the BMW would be slightly better off road
The WeStrom was about $2k cheaper and may be more reliable over the long term.
There are quite a few farkles available for the Westrom,, there are a huge amount available for the BMW.
In the end I bought the BMW and am VERY happy with it. I have over 32K miles now, just changed the chain and a new set of plugs last fall. No other repairs but tires (about 10k miles a set). Likely new front brake pad this coming summer.
Have fun chosing