I've had the H3000 in my system for several years; it replaced a Manley Steelhead (that had some serious tube rolling done). If you don't need the variable EQ curves, my bet (and I have not compared, just hypothesis) is that the H3000 without the extra variable may sound better. Agree with Christian re the rectifier tube- they aren't terribly expensive. The unit also needs to burn in 100-150 hours with music playing (I used one of those RIAA adapters to run a CD in constant rotation, in addition to playing music normally through it, to hear the changes). As to noise, I use 104db efficient speakers (Avantgarde Duos) and you can hear any nasties. I did have some tube noise from one tube, which Allnic quickly replaced. Some listeners find the sound of this unit to 'burnish' the signal; others find that it lacks detail. I don't suffer any of that, but I think it is listener and system dependent. Individual instrument placement is excellent, as is the ability of the unit to articulate the dynamics of individual instruments. I don't want to wax poetic about it, nor am I in the habit of telling people "buy it because I like it." One other thing- fooling around with physical isolation of the power supply makes a difference too; i think I wrote about some comparisons here of different 'footers' under the power supply a few years ago; I use the Stillpoints, which achieve a nice balance between the extremes of adding clarity without stridency. Also agree with the Rockitman that if you could try a burned-in unit in your system, it would make sense before you buy.
Good luck.