A couple of things:
The titan's (or for that matter, the sabre's) so-called advantage of armor is a joke. Titan gets an extra 2700. The total amount of damage an eagle can take, with lvl 10 brigandine shield, is 18180. In other words, the titan has an increased damage tolerance of roughly 7 percent, wow. This doesn't even include the nanos/shields, which brings it down to less than 0.04%. Add to that the fact that the shield is regenerating at a rate of 187, AND that most guns do double damage to armor compared to shield and the advantage goes out the window. Now, the -real- Titan's advantage is the ability to carry more nanos/batts, but even this is flimsy. Basically, if you add up the total armor and shield a titan and an eagle gets, you get 55200/29580 and 47700/27180, a rather insignificant difference, once you remember that, again, shield is regenerating at 187/s. Of course, this is all pointless, since the Titan's extra armor and shield will -never- come into play except for in PvPs, while the Eagle's advantage can be used anywhere.
Now, on to Sabre's turret. The damage on a Nomad blaster is 635/317 at a reload rate of 4.00. The Wyrm is 652/326 at reload rate of 3.03. That's a whopping 14111/7047 damage/s. An extra 1956/976 damage/s from a Salamanca turret (489/244 at rate of 4.00) is not going to turn the tide of battle.
Now despite all of this, I actually like the Titan the best. However, the Eagle is clearly the best of the three, and you Sabre fanboys who think that little extra bit of manueverability doesn't make a difference have never played a true space or combat flight sim.