Noticed the very agreeable pricing out there on the HD555 these days. Is the HD555 still in production, or just being sold off? I know Sennheiser's brought out the new 558 & 598 as an upgrade/evolution of the 595, but I don't see a new model aimed at the 555 niche. You know ... mid-priced, 1/8" jack, easily driven by a portable player. I don't have any serious objection to using a 1/4 to 1/8 reducer but I'm hoping the 555 will be available for a while longer. What other open, circumaural, 1/8" jack, amp optional, $100ish or lower option is there that measures up to the 555?