About two years ago we went from a Citation I to a Sabre 65. Our Sabre has low time, was RVSM'ed in 1999, and has most mods or upgrades. About 80% of our maintenance is inhouse. I only know of 3 shops ( 2 in MO & 1 in FL ) that know Sabreliners well. The Sabre 65 has many more systems that require maintenance than the Citation, but our mechanics like working on the Sabre much more than the Citation.
The big Mx on the Citation is the phase 5 due every 36 months. On the Sabre 65 it's a 60 month inspection. Both about the same cost, but not as frequent on the 65. The CAMP cards are much better (and more expensive) than CESCOM for maintenance personel. With CAMP we have maintenance due every month, but it's nothing our Mx guys complain about like they did on the Citation.
The 65 burns more fuel per hour than our C-501, but on all trips we burn less fuel in the Sabre than the C-501 because it's so much faster. At FL400 and ISA +10 we do .80 burning 640 per side. MMO is .83 and if it's not too hot can set off the clacker in cruise at FL360.
Sabreliner Corp. supports the Sabre well. According to the latest survey much better than Cessna or Raytheon.
I have no experience with the Hawler 700, but talking with people, know the Sabre 65 is faster and maintenance cost are less due to the wing inspections on the Hawker. Both aircraft have the same engine and are the same age. Product support is better on the Sabre, but more shops can work on the Hawker. Try to fly both.
HEADWIND