IMHO, HHKBs look so much nicer when they've yellowed!
I love yellowed one much but don't also mind pale white one at all
I don't know pro2 get become yellowed. Topre may use better plastic for pro2?
hasu, how is the older hhkb holding up? Is there much different on the feel compared to the new one?
10 years. Pro was made in 2003 or 2004, not sure because it has slip-stop sheet all over bottom while pro2 production date is 2010/08.
I lubed my pro once with overhaul completely 2 or 3 years ago. I must say Topre switch feel never last forever without occasional maintenance. If you lubed your Topre can keep its feel as if almost new. I can confirm that.