Anyone have one? That's what I'm looking at getting once I have my first paycheck from my new job.
From what I've heard it's really good for smaller cars, and the carrier seat we have now (A Safety 1st AeroLite LX Travel System) is seriously bulky and a pain to deal with. We'd keep that one for my mom and MIL's cars when they have her and the convertible seat would stay in my car.
This is the carrier we have now:
Not this exact one but the same line.

Should we just keep the car seat we have now and keep switching it between cars when she's going with someone else? Or should I spend the money on this seat?

I don't have one, but it's the seat I am planning to get. I've seen great things about it.

It's a good seat for what it's worth, small cars.
But you can get longer lasting RF seats for the same price, that you can just install more upright.

while its a good seat, and very well liked from what ive seen/read you can find something that will last longer.. the safety 1st guide 65 can be found for under 100 dollars and has a 40lb rfing weight limit and a 65lb forward facing.. on the guide you can adjust the headrest and rear face until the top of the childs head is at the top of the headrest in the highest position, its also made for compact cars