I have a Jack Russell Terrier, and I would recommend anyone to get one. He's over 3 now (my avatar picture is a recent pic of him), so he's grown out of the puppy stage, and chilled out a good bit. He is the most loyal dog I have ever been around. They can be entergetic, but not to the point of where it gets annoying. He is very agile, and loves to play with toys. I NEVER had a problem with him chewing on things as a puppy. As long as he has a bone and a toy, he's completely satisfied. I love that he is so small because I can scoop him up and carry him around with me. They are a very smart breed, never had any problems with training him, and he was housebroken after a few weeks. Easily leash trained. He only barks when someone is at the door, and he doesn't snore. I would guess that he's about 8 lbs. (maybe not even that), but he was the runt. (I always get the runt). Not very expensive either. We bought him from a breeder and only paid $350.

Good luck with your decision

Edit: Also very low maintenence...wash, clip nails, brush teeth. Short hair, so no shedding.