I actually just put my OEM Metzeler Sahara back on to replace my rear T-63. No complaints about the T63 - it's just loud and I was wearing it down on asphalt. I really like the Saharas for what they are - a road biased DS tire. They seem more aggressive than the new Karoo. With how well the Sahara does on the street, I'm not sure I would need something like the Karoo. I'll probably get over 8K miles out of the rear Sahara.
I am leaving my TKC on the front as it is quieter than the T63. If I plan on doing any longer dirt rides, I'll put the T63 back on the rear. But for my street heavy DS riding, the Saharas are pretty good. Not sure why they don't get more attention, other than price,