any experience or thoughts on a surly track cog?

I use an 18t Surly cog. No complaints whatever.

Yup. I used one all winter on my mountain bike and despite my near-zero maintenance regimen, I think it's still shiny underneath all that nasty muck.

i believe some have had troubles with surly cogs (along with soma) not being wide enough to make proper contact with the lock ring, leaving the cog open to slipping and stripping hub threads.

the surly website says that they have redesigned them and now the "footprint is wider than before." Is that what youre talking about?

yup! just make sure you get a new one! (i think the 'new' models started in 2005).

nice. thanks.