I just got 70 Dungeoneering and have enough tokens for an Arcane Stream, but I was wondering, is it worth it? The only thing I do at the moment that I would use it for would be to mage Rex, but in the future I will be looking to burst for higher mage levels and also for a yak. In that time though I would probably be able to get a rapier or cls before I'm ready to burst, so should I get it now or save for rapier/cls and then get tome of frost and arcane stream later?