As good as the original in my opinion. Along with the case and blank key, also included were 5 screws (which is one extra), a Duracell CR2032 battery, and a new RFID chip which I did not use. I transferred the motherboard and RFID chip from the old key fob to the new one and it works perfectly.
buttons no longer worked on old fob. Simply replaced shell with this one, and buttons worked again.
See detail on lexus-replacement-shell34