Some parts of the explanation are technical in the sense that I'll assume you know which hybrid gems are more worthwhile, how you should be gemming in general and that you're familiar with the Orc itemisation list.
1) Replacing tosks with bracers of the heir sims worse for the set Gnimo has given (yes I did change sockets appropriately).
2) I'll assume we can utilize all the stats from the two wrists when swapping them, which we can in a full set. With the EP points Kahories gives for each of the stats that the two items have:
AP - 1
Strength - 2.8
Agility - 1.6
Crit rating - 2.1
Arp - 3.5
You can simply multiply by whatever stat amount each item gives to get a rough idea of how much each one is worth on its own. These EP were simmed without a wrist equipped for the Orc itemisation build Gnimo has posted.
This is a good start, but when we look at gemming we will see that with tosks you can utilize one more yellow socket with a hybrid, whereas with bracers of the heir you will have to sacrifice that exact yellow and gem a +20 arp in it. This means that you're effectively swapping out 14 str and 10 hit for 10 arp. Now with such a high arp rating armor penetration is better than strength by a considerable margin point for point (as seen in the EP), however since it's 14 vs 10 they're about equal in the end, but the extra 10 hit from the hybrid will more than seal the deal in terms of which gemming manages to utilize more stats.
To summarise, when simming the DPS for both wrists tosks comes out ahead. It has, as a whole, "more EP" than bracers of the heir and lastly it improves the quality of your gemming and I can't stress enough how much this matters at such a high gear level.
Edit: You don't need to take my word for granted. Feel free to find the sim, download, set it up and run it yourself.