I have considered and still occasionally do a change the other way but this is how it goes for me, I came from BMW to the S10 for a number of reasons none were the bikes themselves. On the way to places it’s all S10; powerful enough, comfortable, great on fuel (4.6lt/100km over the last 8000km), carries loads of stuff if required and its way lower at the seat. Then it’s onto the dirt and again the S10 is the bike, until sand mud rocks then it’s I wish I had something lighter and the F800gsa is the one, definite going to do it when I get back. Back on the open dirt the F800 can do this just as well but by the time I am home again, the S10 reigns again.
Reasons for change:
An illogical thought that the F800 would be better on fuel; it has a bigger tank so it gets slightly further but appears that its fuel consumption is no better, cure, a Rotopax?
Lighter and undoubtedly better in those few situations mentioned above.
Reasons to not Change:
There is very little reason to change the S10 has to be the best compromise for distance comfort and ruggedness. I need to find no more capital to invest in a BMW, a choice of local dealers and as I have found as a non-mechanic the Yamaha is way cheaper to run.
Outcome:
Still on the S10 love it almost all the time I ride it and still finding/making bits to bolt to it, best GS I have owned is the S10.