Any real difference between 2008 Zipp 808 versus 2010 Zipp 808

Only difference is the hub.  In 2009 Zipp went with the 88/188 hubs. 

Yes.

Having toured the Zipp factory last year before it moved from Indianapolis, Indiana to its new home a few mile away I saw first hand how Zipp's U.S. construction and quality control works.

Zipp makes changes to lay-up, composite curing, testing, design and other aspects of the wheel's construction and manufacturing on an on-going basis. As a result, newer wheels often include small changes from structural and performance oriented to cosmetic and aesthetic, that the company does not publisize on their website. They simply make the running changes and ship the product. The primary reason they do this is to protect the value in landed inventory at dealers. So the evolution of the product is often somewhat quiet.

At one point an enterprising lad built a website that tracked all the Zipp changes during the previous model years as a resource for those buying from the secondary market. I believe his website may have been closed but am not certain.

While I (nor anyone) can't tell you without seeing the wheels or having the wheel's date of manufacture exactly how the wheel is built, what the lay-up is, the hub configuration, etc. it is safe to say some material differences in wheel manufacturing did take place between the 2008 and 2010 model years. Whether those differences are important to you is your call.

You might do well to focus on the mileage and care of the wheels- those may be easier to track from the sellers.

Also- be aware of the recent sweeping design change that include Firecrest rim technology, a complete re-design for Zipp. Pre-Firecrest wheels have lost a lot of value in the Firecrest marketplace since the introduction of the new shape in 2010.

Best of luck with your project!

1300-1400 seems pretty decent. 

Sometimes you can get really good deals on them. I paid $350 for my 2008 808 rear with tire.