Assuming you are asking about 1st Ed....
1. Nolo Tar
Pro It's a perfectly decent Skirmish ship
Con - It doesn't fit in with the ISA combat philosophy at Lower PLs it's not manouverable enough, a fleet of Nolo Tars on their own might work but in an ISA fleet they'd be fire magnets
2. White Star Carrier
Pro Excellent weapons in all arcs, and a decent Beam. Fleet carrier, d6 self repair and more than enough crew to make that worthwhile, plus 8 deadly little fighters.
Con Well it's not as manouverable, but it can afford not to be. There are no real cons
3. White Star Gunship
Pro Errrrr well it's well armed
Con Poor dodge means that it actually has markedly less survivability the the WSC2 it has more hull and better DC but the crew is not much better. Frankly there is no reason ever to take it over 2 WSC2
4. White star Fighters
Pro Excellent Fighter
Con Horribly expensive, I'd only ever take them as the complement for a White Star Carrier
5. Bluestar
Absolute Beauties
Pro Hard to Pin down and Kill, compliment the WS beautifully, can zoom past or even through an enemy battleline and harrass it or threaten a flank
con Short range and few dice means they have to close to shoot and will struggle against interceptor equipped fleets
Of course this is just my opinion, but I have used all these ships and this is how I find they play.
Rgds
