Advance Class Change: Good or Bad idea?

they do not share much. They share a story and a very few abilities.

It would of double production time to make 16 unique stories instead of 8. They devs have said the first 10 levels are a tutorial to the game then you pick your class. Why can you not understand that other then you do not want the truth to be true because then you have no basis for wanting a free new toon.

its been explain over and over and over and over again. What is wrong with you?

If they were different, they could still share the same story, with some minor differences, but there isnt.
Thats not even it, all troopers make the same decisions during the game, they use same companions, same background, go to the same vendors, use aim, use a gun (bigger or smaller, similar to consulars, they both use a saber, ones just bigger then the other).

See, you are the one twisting words to make them fit. "basically calling them specs"

YOU are the one calling them specs. People have posted scripts from the DEVS OWN POSTS that advanced classes ARE SEPARATE CLASSES. No amount of word jamming from your end will ever change this FACT

Ok in wow ret paladins and warriors use the same stats... so i guess they are the same class.

NONE of your arguments hold water man. Also you can play a Dark Side Commando and a Light Side Vanguard and BOOM! different stories.

I know I replied once, have more to add, this is from the actual swtor site.
Consular:
In a more peaceful age, Jedi Consulars may have humbly dedicated their lives to service as keepers of Jedi lore or as ambassadors in service to the Republic—tasks for which Consulars are uniquely qualified. However, as the shadow of the Empire has spread further across the galaxy, Consulars have stepped up to face the darkness on the front lines of battle as often as they’ve faced it when exploring the mysteries of the Force. The Consular’s powers go far beyond meditation and mediation, and nothing illustrates this as vividly as their graceful movements in battle. Whether beset by an army of assassin droids or caught in the middle of soured negotiations, the Jedi Consular fights with an open conduit for the Force; manipulating massive forces to disable or even destroy their enemies.
Knight:
The Jedi Knight’s graceful movements are awesome to behold. Freezing a moment in this display captures the deep commitment underlying the Jedi’s dazzling abilities. Though a Jedi Knight’s life is filled with battle and adventure, the Knight’s heart is dedicated to peace and service. An ironic observation to some, but greater wisdom suggests it is the Jedi Knights’ humble devotion which makes them so likely to become such famous heroes. Whether defending allies by deflecting a barrage of blaster-fire or charging in to challenge a Sith Lord, the Knight’s role is crucial in any conflict. The Jedi Knight enjoys the benefit of ancient teachings that have been passed down through hundreds of generations. Combining these time-tested maneuvers with the natural guidance of the Force, the Knight is capable of achieving extraordinary feats.

What is the difference between a vanguard and a commando again?

Lol see your twisting my words, im showing many examples of why they arent different, you decide to take one example apply it somewhere else and try to make it seem like im comparing similarity based on one feature.

If they were different, they could still share the same story, with some minor differences, but there isnt.
Thats not even it, all troopers make the same decisions during the game, they use same companions, same background, go to the same vendors, use aim, use a gun (bigger or smaller, similar to consulars, they both use a saber, ones just bigger then the other).

this thread is just for opinions why its good, or bad, if you have something to say why its bad or good say it.

Okay then.
Beyond the fact Bioware says no, then...
I have every advanced class, on the republic side. Also one of each of my favorite of the advanced classes on the imperial side.
The play styles between specs are VERY different, in each advanced class, just to start off. (And yes, even though they are mirror classes, there is a difference between Imperial and Republic character classes, too. Though the difference is so slight as to be barely noticeable, unless you are paying extreme amounts of attention)
You do not play the same way playing a Jedi Sage Healer, as you do as a Jedi Sage TK, even though you gear them the exact same. (It should go without saying that playing the balance spec is different from those other two as well).
Now, having played the balance spec on both Sage and Shadow, I can tell you that it's a very different playstyle just between those two, even though that tree is shared between the two different advanced classes.
They aren't actually the same class, because the playstyles (rotations, optimal ranges, etc) are very different.
You can't just switch between the two and think "Oh, I am gonna be just as effective in this advanced class, as I am in this other advanced class."
Because a good portion of the abilities are different. Some of the priorities are different, in the shared abilities. Even in the shared talent tree there is a huge difference in how to play the differing advanced classes.
Now, going beyond the shared tree, it becomes 10 times more apparent how different they are.
It's not like switching from Tank to DPS on a shadow. Those two are very similar, with only slight differences.
It's more like switching from a Mage to a Prot Pally, over in WoW.
It takes time to get to understand how they work.
And the best way to do that is to run them from 1 to max level.
(Mind you, you still can do it, but it will take much longer than just leveling a new character)
They really aren't the same, even though they are listed under the same original class. (IE: Trooper, Consular, Jedi Knight, Smuggler, etc)
If you really think they are, I dare you to level a character without choosing an advanced class until you hit max level.
You will see what I mean about the playstyles being so very different, in a huge contrast to leveling after picking an advanced class.