Unscrewing a rounded allen bolt I need to take out my rear shock but one of the 2 allen bolts that is holding it (the upper one) has been rounded.





I've been told about various ways that such a bolt can be taken out including:


hammer a torx in and unscrew
drill a line using a dremel and unscrew with a screwdriver (I don't think the latter will work, the bold is too tight)
hammer a larger allen key in and unscrew
drill the hell out of the bolt (I don't want this because I'm afraid I'll damage other parts of the link (bushings etc)


What do you propose for this case?
I'd try a screw remover like these. You'll need to either get a set or bring the bolt in to make sure you get the right size (Sears sells their own version that's supposed to be excellent). The good ones have a left-hand thread and a small cutting head to bite into the bead of the bolt; this looks like a really good candidate for a screw remover since the head is nice and large and has enough material for the remover to be able to grab.