Well,
the 5.5 mil you are talking about are not correct. 5.5 payed the last operator buying a XT because of many special options. BUT:
XT and XPR idea is:
Buy an older horse 400A for around 600K (and thats not the 10.000h birds - actually you can get 4.000h with 4 PL4 tubes for around 450K) or pay 1.5 mil. for an NJE 1.500h bird.
Than pay around 2.6 mil to XT nextant or XPR hawker and you have a great competitor.
Difference between XT to XRP:
XT startet to upgrade process and therefore I agree : the cockpit looks a bit piece to piece work.
the new XPR cockpit is something new. Hawker learned from nextants errors and made it look like one nice piece. The screens and panel have the same color. They changed the peanut gages (Stby instr.) to one nice L3 stand allone digital one. and the whole panel locks cleaners. + XPR will increase the wingspan and you get great looking winglets as well to increase performance again.
XT and XPR produce a bird with new avionic, new engines and mostly new cabin.
YES: the fuselage is old. Yes there is still a crappy fuel system with no pressure refueling.
But have you ever tryed the new CJ4? The performance is comparable. The Cabin is better (depends on your customer and how you change the seats and cabinet for eg) and the CJ4 price is more than doubbled.
But 2.000NM range with .775 and a great PL21 with IFIS and total paperless work in cockpit is great (yes - there is still a paper flight log
)
I have flown more than 25 diffrent birds in the Mu300/Be400 series and never had a problem of leaking. I don`t know who is your mechanic, but our birds are parked in a hangar with white bottom color. And so the boss sees every problem of leakage. But we never had one.