now coming from a druid i am a stam whore so i am leaning towards double stam trinkets since i already have the def min (YES ITS A MIN NOT A CAP)
i have no defense gems either, except the meta but i am a shield block whore on my warrior so i wont be changing that till i get either of the non set helms (10 man horseman or wherever the 25 man one comes from)
I'm not much of a number cruncher but overall here's what I see the differences are:
+81 Stamina. Increased health pool is always nice.
+430 attack power for 10 seconds (roughly every 60 seconds). Increasing your dps is fun!
+84 defense rating. Getting hit less is a good thing.
+3025 health for 15 seconds (once every 3 minutes). Larger health pools are also fun!
The base stats of these two trinkets fall on either side of the Effective Health/Avoidance debate. The Sonic Booster gives you more effective health, the Repelling Charge gives you more avoidance. The one to use kinda depends on a)what the rest of your gear is and b)which side of the debate you fall on.
The special abilities of the trinkets are different. One procs to give you more dps, usually about once every 60+ seconds. The other you can use to increase your health pool once every 3 minutes. The one to use depends on whether you want more attack power or you want more health.
Hopefully this helps you make a more informed decision.
Well the booster is a lower item level so you are getting less stat points into that trinket. When given 2 good trinkets, just different uses, the higher item level is usually a good call if you're not sure, IMO. Keep in mind the type of fight - it's all magic damage the static stam trinket is best, but if you are getting hit alot the Defense is much better.