It the EXACT same trem that you have on your LUKE. All the MM vintage trems are exactly the same, and they can be set up to float without any issues just like the LUKE guitars (without the piezo). I have mine floating even with the piezo and have no issues whatsoever. As a matter of fact Albert Lee has his floating as well as I found out in one of his interviews.
Yeah - I will tell you - I have no tuning issues whatsoever with the Luke or JP. As far as tuning stability, I would almost hold either up against the Axis.
I used to hate floating, but I have really gotten to enjoy its wiggle and fluidity alot.