dude, regardless of where england stands in the ranking, australia plays all sorts of opponents, so the type of batsmen warne bowled against varies. you cannot question the variety of batsmen warne has faced over the years. the current english team is just one of many.
to even question the integrity of 'the ball of the century' is just un-australian and you're making yourself a laughing stock. the ball turned no less than a foot and bowled between the bat and pad of the english captain. sure gatting was surprised, but it doesn't take away the fact that it was a beauty.
the fact that warne is a part of the best bowling attacks in the world can be a con and a pro in this argument. no doubt that mcgrath, lee and gillespie (for a long time) provided him with great situations where the batsmen are pressured to the breaking point, and on many occasions warne can just do the honours of tumbling the batsman.
HOWEVER, it must not go unnoticed that on occasions when the team is under pressure, the quicks are not firing and there are limited runs on the board, warne comes up with the goods. the greatest example i can use is the 05 ashes, mcgrath was out injured, lee was out of form, dizzy was on a slide, yet it was warne who managed to take 40 wickets, giving aust the chance. had aust won the game in edgbaston, then warne has single handedly won the ashes for aust. i can give you more examples, such as the recent test in adelaide, where warne took 4 wickets in the 2nd inning. but you get my point.
on the other hand, the bowling attack of sri lanka basically rests on murali, think of the times when murali fails to take wickets and sri lanka got hammered. sure charminda vaas and co has done some work, but it is nothing compared to SL's reliance on murali.
if you still think murali is a great bowler than warne is, using the same logics and reasons you've given, then you're making a mistake. BUT, everyone is entitled to their opinions.