I had both on my previous GS. GSAP is great when used for fast road riding.
Keyless is actually a pain if you have the Satnav - you need to use the key to lock/unlock the Satnav, and then you have to unzip/zip your jacket to put the key in, instead of just putting it in the ignition and turning the bike on. So you have an EXTRA step to do with Keyless. And if you have the key coded panniers, then you still need the physical key. Keyless just means you lack the ignition keyhole to actually keep the physical key on the bike!
Also - there is one place in London where the radio interference is strong enough to fool the bike into thinking the bike has lost/detached from the key. It comes one once you've passed the area, but if you stop the bike in that region, it won't start up again. These kinds of issues show that the system still needs work. (if anyone is wondering, it's the traffic lights next to the cement plant just outside of the Limehouse Link tunnel...)
I'm about to order a Triple Black, and I will not be getting Keyless this time round. It's a PITA.