All the Hornet drivers here, if I'm a Citation X pilot
with 4500+ hrs, how difficult is landing a Hornet ?
I imagine the ONLY place one can acquire training on
them is in the Navy (Marines included).

The F-18 has perhaps the most benign flying qualities of any high
performance jet aircraft. X-wind landings require a particular technique
(as Woody states). Otherwise, it's difficult to hurt yourself if you honor
its envelope, know your procedures, and have a well-maintained airframe.

The big issue with any high performance military jet is getting it airworthy
and keeping it airworthy. Warbirds can be had for ridiculously low prices
(particularly compared to small corporate jets), but getting them up and
keeping them up makes even Travolta's 707 toy look like a relative bargain.
Of course, 1300 gallons give-or-take of JP per sortie (often a particularly
SHORT sortie) makes it pricey as well.

I wonder how difficult it would be to retrofit a nice modern GPS-based nav
system and ILS (not many airports .... any? ... have an operational
TRN-28)?\

R / John