RE: 40 or 60 size kit to build
SIG Somethin Extra Nice and precise, slows to a crawl for landing and can do decent 3D, not the really wild stuff like waterfalls but does hover, blenders, nice flat spins, both inverted and upright, can knife edge into thr next state and all the IMAC routines into the sportsman class
Use an OS46AX and an APC 12.25X3.75 and vertical will be unlimited