I think everyone is waaaay too critical of Gulfstream.
Come on, consider yourself to be a freshly rated 250 hour Commercial-Instrument-Multi engine pilot.
Now you can spend somewhere between 10-15 thousand to get all your CFIs, and then flight instruct for two years, and then apply to a regional...
... OR you can just spend $28k, get high quality training in a Beech 1900, and fly as a B1900 first officer for 250 (paid) hours. Then, you have an opportunity to get hired by other regionals like PNCL or Colgan, or some stay with Gulfstream.
The bottom line why Gulfstream works is that they "hire" you with such low hours, while no other Part 121 regional airline hires at 250 hours. So come on!
This second option saves you time, and time is money! The earlier you get on the airline seniority list, the better!