I think this is just one tiny thing that changed in between the 2015 and 2016 models. My 2015 RT-S requires the 'boot-up' before I can start the engine, unless as was previously mentioned, it was a quick stop for gas.
However, I also have two friends who own RT-Limiteds. The 2015 Spyder requires the short wait to start up - same as mine, BUT the 2016 Spyder will start up as soon as she turns the key. Even if it sat overnight. Now the F3 just came out in 2016, right? So all of those starting right away may have more to do with year and not model.
And for those who don't understand why we are fussing about a 45 second wait? You've obviously never gone for a group ride, been the last one on the bike and then realized you forgot to turn the key before getting on. 45 seconds is forever when your friends are laughing at you!

pps: