is star wars galaxies worth the monthly pay? is it a good game? what are the pros and cons of this game?

If it's worth it is up to you. I'll just give you the pros and cons. I'm only playing the trial right now, so it's not going to be a huge list or anything.

Pros:

• Multiple races
• Plenty of interesting classes, Jedi are surprisingly a minority.
• Plenty of quests, and a main quest you can follow, even though most of these are point A to point B and killing stuff. Still a good way to earn credits and exp.
• Multiple factions. Your alignment with these factions also changes depending on what quests you take and who you kill. For instance, killing Rebels will increase your standing with the Empire.
• Large choice of weapons and equipment.
• Have your own vehicles and mounts.
• Player owned housing.
• Community is still active and is growing since they started fixing the game.

Cons:

• 14.99/mo fee. You get discounts for buying more at a time though.
• Free trial is a 3 GB download altogether.
• No shops to buy new equipment that I know of. It all has to be found through killing mobs, through quests, or by buying from other players through various means. If someone knows otherwise, please let me know, it would be a great help.

Ok there are multiple factions in a way, but the only two you need to worry about (and that really mean anything) is rebel and imperial, of course you can also stay neutral if you wish.

No shops to buy 'new' equipment.. ok, well that is done deliberatly, in order to stimulate trade amongst players.
And although new stuff can be got from quests etc, it can then be sold, bought, traded and so forth- it doesn't degenerate. Just look on the bazaar, the galaxy wide spanning 'trader outpost', which lists EVERYTHING that is for sale and where.