Meh. They have shittier defense than the wolf and about the same attack tbh... They die a lot more since the fellow pots suck ass. Normally I spent half the time grinding spamming fellow potions.
The buff ones are the only decent one imo. I had an attack pet and that didn't do shit. Reason is the 110 skill on all the pets have different activation requirement. Attack requires your hp to be below 30%. Defense requires hp below 70%, and buff is auto on. So the Buff pet increases your dmg almost all the time. The attack pet debuff skill almost never activates unless you're dead, in which case that's useless.
Unless Silkroad has a hole I can stick it in, I prefer spending money on the girlfriend.