Some minimal testing I did myself got me anywhere from about 60 HP restored to wyvern (capped its HP), to as much as 190 restored (did not cap wyverns HP), by using the AF3+2 compared to no hand equip.

Also, I was able to get 3-4 debuffs removed from my wyvern at a time during spirit link, which is nice if it ever manages to get a ton of debuffs thrown on it. (tested in brenner)