I really REALLY love those engines. I call that specific design (the central main thruster [or not, for that matter] with the four auxiliary outer thrusters) the Spride-Type engine when working within my own thing, I love the execution and it's a great craft. The engines make it look really stable.
I'm diggin the engine design! You should probably add a pair of fins to that front pod because otherwise the only place that thing is going is down. I't might be doing front flips while doing it though :D. Destroy!