I did up a 1999 Stumpjumper M2 for somebody and I didn't like that at all, it felt completely dead and quite slow compared to my other bikes. But that was the first aluminium hardtail I had ridden at that stage, as I hadn't built up my Orange E4 yet. The E4 is a different kettle of fish altogether, very fast and lively, but with a great solidity and poise - very confidence-inspiring. I don't know why they should be so different, maybe it's that Easton Elite was the top aluminium tubeset, maybe the lighter spec suits me, maybe the geometry.
At least as far as the E4 is concerned, I don't understand the reputation for a harsh ride. I once rode 20 miles on the E4, got home and went to the shops on my daughter's Lava Dome and I was immediately struck by how the rear of the Lava Dome was bucking up and down, it was like getting out of a Jaguar and into a Ford Transit. The myth says it should be the other way round, but the E4 is as comfortable as you could wish.
I would agree that if you want an earlier aluminium bike, an Orange E3 must be a good bet. Not the same tubeset - despite the Elite and E2, E3 names, the E4 was the first Orange to use Easton tubes - but the E3 is reputed to be a very good, very light frame.