Ben, all companies use the same 'rating' system. your rating should carry from one company to another. your 18 year old friend may have a very low rating, hense the high premium, the $650 excess is a good one if thats the case. all companies have different excess so i wouldnt know if that was full comp or third party. with third party cover, u can still increase your rating, however u may go up 1 rating every 2 years rather than every year, again all companies are different.
hope that makes sense and helps...