Coulda sworn Id read another thread where you'd talked about what you did with your Torpedo, but I couldn't seem to find it, maybe it was all in the shout box...anyways, I was wondering if you'd be willing to share what all you did with yours?

Replaced parafeed caps with Jantzen Silvers. Silvers have more attack and more sparkle. Also more clear and resolving. Huge difference here.

The stock tubes (6J6) are pretty good so I think this comes down to which headphone you use and whether you prefer the hi-Z or low-Z tap. The E90CC is more analytical, less bassy. I've heard some call it more "digital", probably because they have a less organic midrange. The E92CC gets you a mix of both. Very detailed and resolving, and also dynamics and bass explosiveness. But it's even brighter than the E90CC so it pushes the HD800 over the edge in my view. I swap all three of these out regularly.

For those of you who may be flirting with the notion of picking up (and assembling) a flagship tube amp for your hd800's, I noticed that bottlehead is running a major sale on mainline's ($200 off) through Sunday.  Don't think they've dropped this low since the initial preorder when I acquired mine.  http://bottlehead.com/smf/index.php?topic=7581.0

Disclaimer - the build definitely takes some time, and has many many components, but no single step is any harder than building a crack + speedball, and the end result is right up there with the best of the best in headphone tube amps to my ears (having sampled most of the usual suspects: TTVJ 307A, ZD, WA5 max etc. at canjam).  From a design standpoint, it basically ticks all the boxes: highly regulated, constant current loaded, single gain stage parafeed circuit, with good quality iron, se/balanced outs (via secondary tapped output transformers) and bottlehead's awesome custom fine/coarse stepped attenuator circuit.  I'm normally a pot > stepper guy, but the fine/course setup has totally won me over.

Couldn't be happier with mine, although I did end up throwing in some fancy teflon output caps to make it a little more my own when some RTI castoffs, made for AR, were floating around on the market.  In any event, love mine, and apologies for gushing a bit.

shipsupt!  Did you build your Mainline yet and what is the verdict (if you get this query in time)?  Someone has an EC Super 7 with cap upgrade for same price as a regularly priced Mainline in the FS section.  This might be a tough choice but nice one to have.  If I can build a Crack, most people can build a Mainline. 

Dammit guys, stop dangling shiny things in front of me when I have home appliances that need replacing...