the assistant chief was my sim partner at flight safety last year and was a great guy. they have 3-4 westwinds, lear 60, challenger, citation VII, king air 200s. it's a part 91/135 company. not sure what percentage of the flights are which. he told me that they are not a 135 company that is hard up for money and seem to do very well financially. i spent a lot of time with this guy (2 weeks) and can confidently say that if he is there, it must be a good company. they are currently hiring into the king air 200 but there would be quick advancement to the westwind. if you have specific time in one of the other aircraft (along with substantial experience), you could go into one of the other aircraft as well.
i've kept in touch with this guy for the past year and the company is only headed up. if you are considering moving to the houston area or currently live there, i would definitely give them a shout.