too bad I just told my tung-sol's, i woulda offered them to you as a fellow head-fi'er
in the end, I felt the driver tube upgrade to ecc35's made a world of difference. however, I couldnt justify the $150+ for the 5998's - the difference was really extremely small
I couldn't find ECC35s on tubeworld and the ones on eBay seemed pricey to say the least. I'm assuming driver tubes should be matched whereas power tubes it is less important (as David told me).