Both are very good shouts. I honestly couldn't tell you my opinion on what is his best. Suffice to say I think I've enjoyed every film he's ever starred in.
I've always liked Gauntlet, a proper 70s film. Not seen it for a while, but I noticed it was on the other day so I now have it on my Sky box for watching sometime. A bit more recent, but I always like Absolute Power. But really, even though they're quite dated, especially ones like Dirty Harry, I can watch any of them.
Very few Eastwood movies I dislike, the two with the monkey were a bit shit, watched Unforgiven last night and enjoyed it. The 60's spaghetti's and the Dirty Harry series were classics.
Still this.
However the Dirty Harry series was very good too.
Something about those early Eastwood movies made you feel something when you walked out of the cinema. The ultimate cool cowboy, a smattering of Kwai Chang Caine
where total serenity could (would!) turn into tension and a bloodbath hail of bullets, ending with Clint neither shaken nor stirred - still cynically squinting in the sun, merely a curl of the lip in disdain as mean guys lay strewn in his wake.