i've had meeroos and kittycats in the past.. none now, tho. imo, yes they are a pain in the ass, and are a money sink too. they're cute and fun but just not worth it, unless you need something to spend L on.

depends on what you're looking to do... ranges from owning just a pair to having an entire sim full of critters. also if you're just buying/selling/trading.. some species have studding services. So... yeah.