This is an interesting conundrum I have found in games vs the AI at least . That AT's as fast and long ranged as Bombers will tend to totally replace sea transports. Over the long haul they just get more guys there quicker.
Yes, if you build enough AT's but what about armor etc.. You cannot win games if your opponent is making armor units you will need to counteract those units. A few well placed fighters and AA units and the AT threat is all but done.
