It might cost double (I came from an 07 tC) but I can happily say, its worth every penny. Things I miss: Lower payment, 87 Octane, 27 MPG... Things I don't miss: Seeing my car everywhere (seriously, when I got the tC, no one had one- 6 months later, I couldn't swing a dead cat around without hitting 3), Crazy insurance premiums (my insurance rates actually dropped going to the Z - a whole 4 bucks).
Getting into my car is a fun experience now - I viewed the Scion as a lego set for adults. The car basically fell apart when pulled in the right places. Having pulled both cars apart, its interesting to see how much better made the Z is. the tC was a fun car to learn stick on - but the Z is in an entirely different league