Interesting. I have an 1150 ADV with servos - pull brake on, start bike, the servo pump cuts in and you feel the lever move OUTWARDS, away from your fingers, as the pressure from the pump is chimed in. No problems with starting the bike while holding the brake on.
Without the ignition turned on you have manual brakes only and it needs a good pull on the lever to get enough bite, but it isn't something to be frightened of, just aware of when manhandling the bike around. Turn ignition on and you have the sevo assistance immediately - so if you are worried, just turn the ign on before pushing it about and you have instant stoppies.
I also have an ABS NON SERVO 1150, standard one. The brakes are nearly as effective as the Adv with servo, but without the added weight of all the gubbins, and added complexity of the extra circuitry.
Reliability of the servo system has been called into question too. I have never had an issue in the 85,000 miles mine has covered. The same system is fitted to the road bikes and nobody complains, or not loudly anyway. Is it just the GS riders who shout louder? I don't know, just asking. I know big K riders have reported few problems with the servo system and like the additional power for little finger pressure. That is the thing, the brakes are just as effective on both types (same disc rotors, same pads essentially) it is the finger pressure that changes - with servos you can haul a fully loaded bike down from silly speeds very quickly with light finger pressure. The non servo brakes just need a bit more heave on the lever to do the same thing.
My experience is that the 1150 is better than the 1200 - was nearly seduced and had one for a week. Got back on the 1150s and they are more comfy and ride better, FOR ME. I bet you'll find people who think the other way round. So you can only go by what feels right for YOU.