Are there any differents between the cheaps ones and the expensive or they all the same?

Some of them are 95% tungsten, some are 97%.  I doubt the average user really can tell the difference.

Some of the companies offer a higher quality weight though.  They'll have a better finish on them.  On the insert free weights, the inside of them will be far smoother than on the cheaper weights.

I have tried Tur-Tungston and some other brand I can't remember, Lake Frok Tackle maybe.  Anyway the other brand was almost impossible to thread braid through that insert.  I guess mono or flouro would go in easier because it has a stiffness to it, forget it with braid, unless you have a perfectly clean cut on the end and super vision it ain't happening.  The Tru_tungston ones are super easy with a big opening and no insert, plus pegging them is much easier.  For me they are worth the extra 50 cents.  I haven't seen any others that were less than about $5.50 per pack.

By the way, one of the new site sponsors has insert free tungsten at a very good price.  Good quality.  Seems to be right up there with Tru Tungsten.  I'm happy with my first order and will probably be ordering more soon.

http://soldier.heritagewebdesign.com/~trejason/cart/index.php

The Tru_tungston ones are super easy with a big opening and no insert, plus pegging them is much easier. For me they are worth the extra 50 cents. I haven't seen any others that were less than about $5.50 per pack.

That's what I like about them! Also, the painted ones (don't know if you used them), hold up a lot longer than any other painted ones I have used (the finish that is). That may not matter to some people, but it does to me I never tried the Eco-Tungsten ones (the site sponsor) so I cannot speak for those.