Nice cave trolls?

[The Might]

Indeed, they were quite different, and this is also made clear in the Appendix of LotR:

[FONT=&quot]Trolls therefore took such language as they could master from the Orcs; and in the Westlands the Stone-trolls spoke a debased form of the Common Speech.[/FONT]

Pretty clearly, the 3 trolls from the Hobbit were indeed this type of stone-trolls.

The encounter from the Hobbit also happens to unfortunately be the only one with this kind of creatures, so no further information exists. But clearly they might have been less intelligent, aggressive and dangerous then other types of trolls, such as the cave trolls or the feared Olog-hai.

Still, I doubt there was like a "nice" troll, because there is really no reason why there would be one. If they indeed originated from creatures corrupted by Melkor then it is quite unlikely you would find any nice ones, just as unlikely as finding nice Orcs.