Front Focus on Tamron 17-50 2.8

My Tamron 17-50 has developed severe front focus.  At -10 I have it down to about 1/8th of an inch at 50mm but then at 17 it has a small bit of back focus.

Q: Anyone have a simular issue with this lens?  I bought this used off ebay and I am wondering if someone passed off a lemon on me.

Q:  Has anyone sent a lens to C.R.I.S for focus issues?  I tried to do the online estimate thing but it says I need to send it in.  Anyone know the approximate cost for getting AF repairs?

Any other input or suggestions are most welcome.

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Very happy K5 & K200 owner!
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