Allright I tried out most of the things you wrote, especially Saymus advice was very helpful.
So thanks everyone!
But I can't get rid of the impression that I would be better of with a jab, ftilt, utilt or even a fsmash.
Is it like that? Is throwing with Samus just useful to confuse the enemy?
I would like to know situations where the best reaction would be a throw.
The only situation where I could expect throwing as the best answer is shieldthrowing after an enemy arial.
Is that an viable situation to throw or would another action be better?
Are there other situation where throwing is the best thing you could do?
Good questions.
Uh.... yeah it's good to confuse them with. I mean, in a general sense, a slow attack such as her grab is not something you're going to expect from Samus - but knowing this, you can use that to your advantage. Of course people are always getting smarter, so they probably expect the grab more now... meaning, yeah, like you said, "when are the best places to use it."
Shield-throwing after aerial... it seems like up+b out of shield would be best there, unless it's a really slow aerial.
Really, I think your best chances of using it are when they make a mistake, or when you give them no other option than to shield, and you can follow up with a grab, or, when nothing else you could do would work (though... that's somewhat redundant).
So, if they messed up a recovery, or had no other option - say you're both off the edge somehow, on FD, and you're playing a Fox/Falco, and they can bet you're going to up+b back to the ledge - they'll want to side+b back to the stage - say they go over the stage though (messed it up or were forced to somehow) - while they're doing that, you're recovering... basically, you're on the ledge and they've just landed - they're recovering from lag, you edge hop WD to grab and throw them back off again - they're down below, using up+b to recover, and you're on the edge - a perfect place to edgeguard them.
So yeah, that's really situational, but those are the places where you'll best need/want to use the grab.
So... when you land and missile cancel right near them, they either have to jump, dodge, or power-shield it. If they jump, you're not close enough (because they had the time to) and you watch for it... and go from there. If they dodge, you utilt/grab. They shield, you grab. If they're really good at power-shielding (hey, my friends are)... act like you're going to missile, wait for their shield, then grab. (Or, if it's a character that can easily attack you while you're missile-cancelling, fake them out somehow so they shield. And as well, if they're near a ledge, they could WD back to the ledge).
Of course...
Sometimes it's just better to go for a charged fsmash, wait for the spot dodge (or whatever), and then hit them with that - like you said, sometimes it's just better to go for an attack instead of grapple.
(I didn't just go in a roundabout did I >_>)
Some good situations for a grab are when you know you can kill them with it - high percentages on fast fallers - you down throw them and they bounce too high to tech, =fsmash to death.
One other thing... if you're being aggressive and really pressuring them, and then you get them into a combo, persay, and you chase them, chances are they'll shield - so it's times like these when you can grab - even twice or three times in a row (though that's really lucky and somewhat stupid, possibly even unncessary) - and you'll get it on them because they w.ere scared and tried to shield whatever you were thowing at them
Ah. I can't really think of anything very definite to say. (hope i didn't blather too much or something)