It got moved.
I ordered both (on DVD) Wednesday night, judging by E's usual shipping speed, I should have them tomorrow.
I'll post a review of both, and my opinions on what to got.
-Zodiac-
You should buy the download bundle next time...trust me the extra 10 bucks is worth it.
Ok here is my opinion on both (I own them both) under the criteria you posted:
Impromptu-ness
Bullet:Much easier to do Impromptu if you can control your audience, and is impromptu with no gimmicks at all, and the set-up is really 3 seconds like they say.
Factory Sealed:You would have to be a lot sneakier to perform impromptu BUT the coin cannot be signed, where-as it's possible for Bullet.
Reactions
Bullet:Your audience will seriously flip, just the sheer velocity of the coin penetrating will catch them off guard and they'll be amazed. Especially the signed version but, you MUST be able to do it cleanly, if not the effect will be blown
Factory Sealed:Factory Sealed will make your audiences just stop. It is a pulse stopping effect where they will be left stunned and will have NO WAY of figuring out. It is probably the strongest reaction of shock you will recieve.
Difficulty
Bullet: Bullet is basically pure sleight of hand with a twist. You will have incorporate 3 or 4 sleights to achieve this and if they're done poorly, then your screwed.
Factory Sealed: It's much more about presentation and controlling the audience. You will need to know maybe 1 sleight, that's all. It is the simpler of the 2 effects, you just must know when and where people will look.
Hope this helps a bit,
-RA69