Ya, do blackjack for as long as possible on the free $5400.
And hang on, if you have to deposit to redeem the money, why not?
Deposit the min ($10 i believe for here) Play it a bit, Make SURE you dont redeem a bonus on it.
Then redeem the comps, play basic BJ or something to play it through, and cash it out.
If you can get to a couple of hundred bucks in comps, why not? All free.