I can absolutely recommend the bars I have on my Kawasaki W650. They give an ultra comfortable position, which is ideal for big rides out, and you don't feel the aches and pains the following day. The only issue I get with the Kwaka is a sore backside when I've been out for about 5 hours of continuous riding.
The bars on my GF are ok, and I've had a lot of 150m+ rides with them, but I do get a bit of back and neck ache from the riding position. The ONLY reason I've not changed them as yet is because I feel they're more in keeping with the look of the bike than higher bars.
I suppose that if you only do shorter runs, the standard bars are fine. If you want to tour, I'd be looking at the higher bars.