The carbs on a 950 can handle that no problem, assuming they are setup right and have not been messed with. Lots of photos here of guys with them higher.
The early EFI models had iffy EFI. Mostly lacking a smooth throttle response. That was smoothed out on the 2009 on up models.
The 950 had fuel pump issues, but that can be solved with many after market options. The EFI models tend to eat fuel filters for lunch, so expect to replace them (they are in the fuel tank, and not cheap) every now and then. More so if you get bad fuel.
I had my carbed 950 up at 9500 elevation. It was not happy about it with a bit of bog off the bottom, but nothing major. And I have my bike setup rich. Leaning it out a bit would solve that.