Code Blue
Knight
I 5xed a beetle one time. Was dueling some guy out in the farms and got a stun when he had low HP. I jumped off my bug and said all kill while I was loading an ebolt. The beetle bit him to death before I could cast. He didnt have armor on though.
GM resist on a beetle is pretty easy to macro and helps a ton if someone's trying to kill your mount. Also the ranger NPC will let you summon them for like 750gp.
Beetles are so under rated and op I'm surprised people don't have them