I took the bonus. You receive it quicker and with fewer contingencies than loan repayment program (for former college students) or navy college fund (for future college students). These days, other than electing for the loan repayment program, you can't not get a bonus. You can still get $350 per month for if and when you go to college plus $12,000. That is the college fund, I think its called the kicker. The loan repayment program is split into thirds, applies only to federal loans (PLUS, Stafford, Perkins), starts only after one year of good service, and is taxed as well. Further, it is sent only once a year in one payment directly to your lender (s). It also max's out at some number. It doesn't apply to any private loans. So, you have to stay in good standing the other 11 months in order to be eligible for them to do it again next year. That is annoying as there are many contingencies and conditions. So, the simplest thing to do and the easiest thing to brag about was to take the signing bonus. Try explaining the loan repayment program to your friends!
My understanding is you get 1/3 of the full signing bonus, after taxes, after completing power school. Then, you get 2/3 after completing prototype. Fewer conditions are attached and you get the money sooner, that called a liquidity preference.
I presume the bonus+$350 kicker is split like the full signing bonus is, but t may not be. You have to go to college to get the $350(/per month?) kicker. If it were per credit hour, that would be a different story. That's a good deal.