I picked up one of these off Ebay for a very good price and it arrived today;
Although this version is based on the US Marine Corps Osprey, typically I wanted to build a USAF one so you might be thinking “why did’nt he get a USAF version in the first place?” The answers to that question are (1) the USAF version is out of production, (2) the USAF ones that are available are asking silly money on Ebay and (3) all that differentiates the different versions is just one sprue (E for USMC and this Osprey and J for the USAF one).
Having looked online at the two sprues, the differences are mainly confined to the outer tail fins as the USAF version has extra bits nailed on plus there are a couple of different parts to add to the fuselage such as the dome on the nose ( a low-flying radar or something I believe) plus a couple of lumps that go underneath.
However having also looked at reference pictures online Hasegawa missed or simplified a few things too so regardless of which version you want to build, you are going to have to make stuff from scratch. Anyway I got a Wolfpak decal sheet that features a USAF Osprey based at RAF Mildenhall in 2019;
Images of this particular machine show some differences in the antenna arrangement on the upper fuselage plus the addition of what looks to be some type of counter-measure pods underneath the fuselage so these should be interesting to make.