This is a tough one for me. The Mapletree Line 2A (with all upgrades) really transformed my system after coming from integrateds and receivers. The Mcalister PP-150-8 is a fantastic amp that, along with the MAD 2A, really brought the music into my home. And then my GR Research Neo-2X sealed the deal for me. All were handmade by a single individual and because of that are somewhat unique IMHO.
So which would be the hardest to get rid of...hmm...probably the Neo2X because unless I built another pair, there's no way I could touch this level of sonics for anywhere near the grand I have invested in them.
However, I'm also the type that could survive with an IPod and a pair of Ety 4Ps

I have to agree with Zybar about room treatments...while I don't have a ton yet myself, the time spent putting those together and getting them set properly would make them irreplaceable. Just hard to get psyched about room treatments
