I don't see how wanting to be better able to survive the vast majority of afflictions, spells, and supernatural attacks that you know, without a doubt, WILL be thrown at you throughout your career is any way metagaming. Seems like something any character with a gram of sense (or allies with a gram of sense) would do, regardless of how well it fit their theme.
Oh, and Epic characters with the ELH wealth system don't wear Cloaks of Resistance. They wear custom items that give a +5 each of competence, circumstance, insight, luck, morale, and sacred/profane bonus to saves. At least, they do if they want to be able to make the kind of saves that will be thrown at them on a regular basis by creatures of CR above their level-5 or so. Because that's a +30 bonus, for less than a +6 or +7 of a straight resistance would cost you. And a resistance bonus itself is easy to get with spells, so you're stupid to get an item that grants it.
Oh, and Epic characters with the ELH wealth system don't wear Cloaks of Resistance. They wear custom items that give a +5 each of competence, circumstance, insight, luck, morale, and sacred/profane bonus to saves. At least, they do if they want to be able to make the kind of saves that will be thrown at them on a regular basis by creatures of CR above their level-5 or so. Because that's a +30 bonus, for less than a +6 or +7 of a straight resistance would cost you. And a resistance bonus itself is easy to get with spells, so you're stupid to get an item that grants it.