Random Bonus Items From The Shop - How do they work?

I am very sorry if this has been answered already. I searched for a bit before posting this and came up empty... (found another unanswered topic under general, but didn't want to necro a super old post).

Items on the shop that come with a random bonus (such as Ravelosh's Gloves http://tbc.cavernoftime.com/item=9390), Do they send you the best "of the" for your class? (Monkey, Owl, Boar, Etc,) or is it still just a randomized bonus?

Thanks! Sorry again if this has been answered ><

I have no information about it myself, but I think the bonus is completely random.