If you got DFO my guess is your gear is pretty decent, since I haven't seen an armory link I can't really tell you what would be best fro you, but at a certain gear level crit starts scaling pretty good for shamans. My guess would be that http://www.wowhead.com/?item=45308 is better for you.
Try to sim your DPs and scaling with each trinket on simcraft and check the rawr stats for each trinket at your gear level. That should help you out too