Thanks for all the replies. 
The two main reasons for the aircraft chosen is 1) the budget, and 2) company perception. The company flies a lot of customers around and they don't want to get an airplane that is "too big", thinking that the customers will see their investments as going towards "big, luxurious airplanes" for the big wigs. Of course we do have a few customers who have nicer airplanes than us, so go figure. Not to mention, they want to do this, and try to lower costs (the reason for option "A"). The company does a lot of less than 1000nm flights, so option A is there for that reason. Take the small & efficient jet on the shorter legs and the big & efficient jet on long, hot/high legs.
How does the Citation X do high/hot?
The two main reasons for the aircraft chosen is 1) the budget, and 2) company perception. The company flies a lot of customers around and they don't want to get an airplane that is "too big", thinking that the customers will see their investments as going towards "big, luxurious airplanes" for the big wigs. Of course we do have a few customers who have nicer airplanes than us, so go figure. Not to mention, they want to do this, and try to lower costs (the reason for option "A"). The company does a lot of less than 1000nm flights, so option A is there for that reason. Take the small & efficient jet on the shorter legs and the big & efficient jet on long, hot/high legs.
How does the Citation X do high/hot?