Miller.
Despite being unquestionably one of the better bowlers of his time, an analysis of the statistics will show Lillee to be probably the most overrated bowler of all time, and only in about 20th place in the Pantheon of greatest fast bowlers. If Australians like Slow Love or Top Cat want to bring their blatant national bias into the frame again that is up to them, but the fact of the matter is that the team that scores the most runs wins the match, not the team that bats most stylishly or with the most charisma, and Lillee's reputation far outweighs his actual on field performance.
He failed completely in Pakistan, then pulled-out of subsequent subcontinental series - which does say something about his character. He had just one good series against West Indies, the best batting team of his time, and was a failure against them overall. He even failed in Sri Lanka who were complete novices during his time. Marshall, Hadlee, Ambrose, McGrath, Akram are considered by the general cricket media to be either worse or at least no better than Lillee, but they all have far less holes in their resume - performing against everybody and doing well almost everywhere (much more varied places than Lillee).
Lillee is thought of as pretty much the complete fast bowler despite even Rod Marsh admitting that he had a weakness against the left handers and that he also struggled to run through lower orders due to the lack of a good yorker. Lillee was not the complete fast bowler and his reputation as the king of fast bowlers is just another example of Australians and inconsistent matchwinners being remembered more fondly than consistent non Austalians/Englishmen (a la Murali vs Warne where Murali is clearly much better than the overrated Australian matchwinner, yet does not get the credit he deserves).
Please note im not questioning his status as a great bowler, just think he is overrated and not among the very best. Lillee's on field performances are less impressive and FAR less consistent than McGrath even though he played 85% of his matches in the pace friendly countries of England and Australia, and in a lower scoring era. Furthermore McGrath is rarely thought of as the very best fast bowler. IMO Malcolm Marshall is the best paceman ever, closely followed by Hadlee.