Hi everyone, I am new here, I am going to buy an Xbox next week.
first of all, I have heard that all the new Xboxs are V1.6 and do not support any kind of mod chips, so I think it would be the best if I'll buy a used Xbox from the closest EBGames, also I think I'll buy the XBIT mod chip cause it's solderless (I don't know anything about soldering) and I wanted to know what should I do after the phisical installation of the chip, second, I would like to know more about the different DVD drives. third, I would like to know the advantages/disadvantages of installing a solderless chip.
Thank you all.

Everything you just asked could have been found in the forums. It really all depends on what you plan on doing with your Xbox...

All I want to do with it is playing back-ups and emulator games, and watching Divx movies ( from the HDD).

As far as what needs to be done after installing the chip, check the tutorials.

There are other solderless chips other than the xbit. I would look at the xecuter 2.3b lite +. There are also solderless adapters for most including the new "4th Gen chips"

The only advatage of solderless is in fact that, you don't have to solder. IMO there are more disadvantages. They can come loose often needing realignment and I here of many people scrathing traces when they install them. If you can, learn to solder or have someone who can install a solder chip for you. I hadn't done any soldering before I modded my xbox. Practiced on an old NIC, and put it in there. It is not hard.