I'm a fan of the Darkmoon Zep and Darkmoon Tonk myself. For most of my 'pve' pet battles, I use a Darkmoon Zep, Obsidian Hatchling, and a Frigid Frostling (his Ice Tomb hits like a truck).
On the other side of the coin: Pebble, that massive pain in the ass to obtain in the first place, continues to be a massive pain in the ass if you put him on your team -- his hit chance is in the 30-40% range for the initial part of his rockfall attack, and it feels like he misses or gets dodged 10-20% more often than pets of comparable quality and level.