I have used the Original ones from the very beginning. Just don't pinch them with Pliers or something.
You don't have to, but it keeps the Caps from blowing/sliding off and offers a more secure connection.
That was in reference to using the larger caps to block off the air induction ports (to remove the whole air induction system), which are right above the exhaust ports on the head of the engine. It probably gets significantly hotter there than it does at the throttle bodies.
No, I did not use the clips, they fit pretty snug and I have to pull pretty good to get them off.
They're probably not really necessary, especially if the rubber caps are a tight fit, but it's possible to fabricate your own clips from 'springy' wire.
Hear, hear! Not an issue of sturdiness for me but rather durability. I added short vacuum lines from the TBS port because those clips/caps are so freakin' hard to remove. The AutoZone caps I used to plug the vacuum lines were showing significant cracks and all-around rubber rot after only a year. I can't imagine that area of the bike is harsher then any car engine compartment. I can only conclude it's due to cheap rubber, and no one should ever settle for cheap rubber!
