Well i was lucky enough to see both trailers that were leaked yesterday(i know right, how lucky). This is what i think of both effects based on what i saw.
Factory Sealed
The effect looks clean... too clean... i could not beleive it. One second he had the coin on the tip of his finger, placed it under a sideways bottle and he asked the guys if they see the coin and the camera was on the bottle the entire time, he counted to three and moved his finger away, and the coin was inside. It was redicoulously clean. The downside was that i dont recall seeing it was an impomptu effect(it might be, i really dont know) but i would just like to do the effect if i happen to have a coin and a bottle of water, i'd rather not set it up. I also noticed that the only bottles used in the trailer were Dannon water bottles, no bottles of any other brand, and that makes me think it might be restricted to that bottle only.
Bullet
This effect is impromptu, which is a plus in my book. The effect was done with empty bottles in the trailer and they were all bottles with large caps(gatorade and vitamin water bottles) so that might have something to do with it. The entire thing is examinable before and after the effect and looks pretty clean, but the coin was slammed into the bottle. I personally think it would look more "magical" if it was slowly melted into the bottle than if it was slammed in quickly.
So right now, my pick would be bullet, solely because its impromptu but if i find out factory sealed is also impromptu, then i might end up getting both when it comes out.
Hope this helps people clear up the details on the effects. =]