When are Bombers better than Sprayers?

I use Strafers to attack the creeper at its source. I use Bombers to create a beachhead area to make it safe for landing guppies and building out from the beach head. I split the load between ammo for the Strafers and Anti-Creeper for the bombers. On some maps I've played, this has been important. In others, not so much.

While a beachhead area can be created with just Strafers, I find that with the way I prefer to play and build, doing what I described above is safer for the early construction process, as anti-creeper hangs around for a long time, covering the "reload and return to attacking" cycle. I've had large swarms of strafers "sync up" in their reload cycle when I did not include the bombers. That led to frustration as my beachhead was overwhelmed before the strafers got back on station. Using bombers, I have this issue much less often.