Well, there are only three real benefits of the SB, but are these benefits really useful compared to the other negatives?
Positive 1 - it is invisible to galaxy scanners. This means that if you fly a stealth only mission, you are invisible to someone watching on a scanner. This could be useful if flying around some asteroids. BUT - usually an attack will have some transmitters mixed in to carry resources, so they are visible to scanners, Anyone scanning an attack of transmitters that is slower than usual will immediately realise that there are stealths in that attack.
Positive 2 - the target that you attack cannot see the stealth bombers for the first half of the flight time. Again, this benefit is lost if the attack has transmitters mixed in. Only a noob will look at a 25 transmitter attack coming without realising there are stealths in the mix.
Positive 3 - stealths have a first strike capability against defenses. So before the battles begins, the stealths are allowed a first round of attack - but only against the defenses. Problem is that there are very few turtles. Most players have very little defense, and will rather defend by escape flight, or by using their own fleet to do a ninja. So first strikes aren't that great.
Negatives - slow, expensive, soft. There are much better ships and strategies that make the positives of stealths almost irrelevant.
The one area that stealths have proved useful is with vacation mode jumpers. People come out of VM for a few hours, then they go back into VM. A few days later, they log in to find they were attacked while in VM. This is because there are players with nice sized stealth fleets that send a slow attack against someone that has just come out of VM. When the player goes back into VM, they still haven't seen the stealths incoming yet. For this reason, always EF before activating VM....
