Should i join the union?

Sure you are.

So they will promise better wages and working conditions and benefits, but in the end it could be to your own disadvantage.

There are a lot of union employees not working now, or soon in the future, because those benefits caused the company to go broke.
And as you get higher wages, the cost of living also goes up because of those higher wages. So in the end it is a no-win situation.

Several states are in this pickle right now because of the high cost of supporting the retired.
Just look at CA.

 

And people in Hell want Ice Cream too...But..both ain't gonna happen.....

 

Look at Greece....Over 80% of the workers were union.....