I'm on DDMtuning.com looking at the HIDS and just wondering whats the difference between the slim ballast and full sized ballast, and it has the options of adding the error eliminator, adapter cables, mounting brackets, and the harness what do i need out of them to have the HIDS last the longest and be the most reliable? also is this the best place to get HIDS and my car is an 04 so i'm not sure if anything is going to cause a problem. Thanks for the help in advance, and sorry if this is a repeat.