Enhancement PvE trinkets?

Hi, I have a few questions regarding enhancement shamans and how to improve their dps. My shaman's name is Grimlic, I play on Raganros on the horde side. I have grinded myself to a 6k gearscore and consider myself a decent dps.

The armory doesn't seem to want to work right now so I can't link mine. My current trinkets consist of the herkuml war token and whispering fanged skull (will eventually become heroic version). Which leads me to my first question: What are the BiS trinkets for enhancement pve?

Also how good is DBW for enhancement? The armor penetration would be almost unnoticeable but the 30 proc would surely make up for it?

I'm considering donating so I can avoid the server queue at peak hours and I was considering buying DBW with the coins. I understand it may not be the best choice, but it is almost impossible (unless I ninja, but I'm against that) for me to obtain in-game as I only really do Pugs.
All other gear I believe I will eventually obtain over-time, whereas DBW seems unlikely for me to ever legitimately get.

So my question is what would be the best item to donate for? (Look up my armory when its working).
And how good is DBW for an enhancement shaman in pve and pvp?

Thanks guys

WSF or STS are better choices. For WSF, crit rating is an awesome stat for an enh shammy, even past cap since it pushes glancing blows off the way. For STS, yeah... it's STS ffs. If I was you, I'll donate for a weapon (Havoc's) since enh scales better with them.

You wouldn't benefit of DBW as much of other trinkets. Best trinkets in order are: Herkuml War Token hc, Sharpened Twilight Scale hc and Whispering Fanged Skull hc. So if you are going to donate for a trinket i think it's better to go for STS, or as said by CombatBunny go for Havoc's Call that scales far better.
Armor penetration doesn't scale very well on enhancement as we only do roughly 35-40% of physical damge.