So is Porcupette worth leveling to 25? Not sure how well his abilities will scale at that point.
I personally have been using this one since I got it after my second pet trainer battle (and I never have good luck with drops). It has really good health and has awesome critter damage, plus it seems a bit more resilient than other pets I've had. Also (spolier!) since it's blue, I named him Sonic, though I know it's supposed to be a porcupine, but when you get to level 20, you unlock the secondary skill called "Powerball" which does 171 critter damage and increases your speed every time you use it. It's ironic because I renamed him back at like lvl 7 :P