Wow, I'd totally missed this thread up to this point (too many "Battle" threads out there).
I actually saw a fair bit of these guys (it's very hard to rate some of the more historical figures, I find - it always seems to rely on pure stats and how much purple prose has been devoted to them).
I'm going for Malcolm Marshall in this one. Awesome strike rate, incredibly fast, and one of the greatest fast bowlers in the history of the game. He was also terrifying, and had this weird habit of coming down the pitch screaming if he bowled somebody - I think if I'd ever been one of these victims, stumps in disarray and with him coming at me, I'd have turned around and ran. A pity he died so prematurely.
Ambrose was an excellent bowler - and I'll always remember that amazing spell in the first innings at the WACA in '93. By that stage, it was just adding insult to injury, 'cause we knew we were stuffed going to Perth at 1-all after not managing to win the previous test. I admired him but didn't particularly like him - he always seemed to me to be a little overly aggressive in his behaviour in a way that definitely wouldn't be considered acceptable today. Steve Waugh's confrontation with him in the face of his intense physical intimidation and hostility was one of the greatest moments of Australian cricket, IMO.