you get everytihng with the plane except for electronics and turbine package. All gear, valves, tanks, hardware, etc comes with the plane. For a P120 i would also opt for the larger hopper tank ( the Kevlar center hopper ) .. the clear canopy and cockpit kit add a lot to the apearence of the plane as well. The plane performs perfectly with a p120 or equivelant class engine. If you are concerned as to overspeeding it, id recomend getting the air speed sensor / limiter option from jet cat, and keeping the RPMs on the engine at max, giving you unlimited verticals, and rapid acceleration out of slow flight. Here are some videos of my BobCat which weighed in at around 25 lbs flying on a P120 both off of grass, and pavement. The red BobCat in the 3rd and 4th videos is Adil's, and at the time was powered by a p80.
http://www.youtube.com/watch?v=rWMrl1CLj8Y
http://www.youtube.com/watch?v=Zr48ZxWcMbU
http://www.youtube.com/watch?v=RpF3nE_haIk
http://www.youtube.com/watch?v=omfe6mhWNxI
this is my BobCat flying now wih a 36lbs thrust JetCentral Rhino ( structuallt modified to handle this power )
http://www.youtube.com/watch?v=cZnyN5Otc9U
these should give you a good idea of what to expect from this plane .....
Voy