I keep my clear shield in the pocket of my jacket. It is a PITA to swap... four fiddly bits have to be removed from the helmet to get the shield off, then you've got to keep various bits aligned as you put the other shield back on. And of course if you want the anti-fog thingie, you've got to swap that too while the shield is off.
I've done it a few times already. Usually because I stayed out later than planned with friends. Did it last night while sitting on the bike (in a gas station parking lot) after pulling off the interstate because it was getting into "debatable" time. What sucks about that is the shield pocket can't really be used while you are wearing the jacket so I had to unzip the jacket from the pants, take it off (which meant taking my gloves off), work the shield out, disassemble and re-assemble the helmet (using my jacket as a work surface), worm the shield back into the jacket, put the jacket back on, zip it back up, put my gloves back on, put the helmet on, restart the bike and ride away.
Still only took about five minutes. I'm probably could've shaved a few seconds by getting off the bike actually, but I wasn't in a hurry.
You'll get used to it. I've heard the Arai system is actually pretty OK once you figure it out.
I'll probably do it again tonight, depending on how traffic is. Lane splitting is fine, but I've got to travel one of the main roads between LA and Las Vegas, and traffic on Friday nights ahead of 3-day weekends ... I don't even want to think about it. Parking lot until 2AM nuts for a start. In a car I'd consider it amazing if I could get home before 2:30 in the morning. We'll see how it goes on the bike.
Ride it like you think owning it matters.
