A couple of month back, in my rush to assemble my zkit 4/5 and have a listen, I ended up assembling it with all kinds of errors that would make some of you guys cringe.
And as expected, the unit hummed and buzzed like hell.
So last week i went about reassembling it, making sure ground paths are clear, twisting the cables, etc...
So i hooked it up to my SE34-I, running a single mullard el34 per side, connected to my Audio Nirvana super 12 drivers (rated at 99db/1w/1m) in the regular large bass reflex cabinet, that i always thought lacked some serious bass.
And
hmmmm
WOOOOOOOOOOOOOOWEEEEEEEEEEE
BASS, tons of it, not overpowering bass, but rather, crisp, tight, coherent, audible bass!

For the past month I had been looking at getting a pair of Klipsch La Scala's (fully horn loaded, three way, rated at 104db/1w/1m) hoping the higher efficiency would solve the anemic bass (and I must admit, I love the looks of those beasts), but after having a listen yesterday, I can safely say that i'm cured from upgraditis (at least for the foreseeable future).

And btw, after the initial excitement, I took my time to test for hum and noise: there was none, even with the SE34-I cranked all the way up, goes to show how important proper grounding and wiring paths are....

Conclusion: Zkit4/5 + SE34-I = heaven.
Thanks Steve for the great products

Next step: try and swap in 6922's in place of the 12AU7 in the Zkit4 (after modding the heater circuit so as to drop the voltage to 6922 friendly levels), I've heard they sound better, will get back to you with impressions.

Below are some pics of the setup (pardon the cheapo, blue generic interconnects, but my 2nd pair of DIY CAT5 interconnects was nowhere to be found)