That's a wicked price. I have an early 2011 13" MBP with 8GB ram as my daily driver. I do all my computer science work on it everyday. It's incredibly reliable and even survived being soaked from a leaked bottle.
I use the thunderbolt port with a 6TB external drive and an Apple Cinema Display daisy chained on. Ethernet is nice to have, as well as a CD drive for the odd burn and even a FireWire 800 port I use for my iSight camera.
Probably the best model for backward compatibility of hardware VS power of a modern Intel machine.
I would highly recommend.
Damn, I miss my 2011 15". My perfect Mac ... if only the GPU hadn't been made of chocolate.
Unless you buy a Thunderbolt Dock, the rMBP requires lots of bits hanging out of it to add back the functions they stripped out to get it a couple of mm thinner. Nice machine, but compromised for my usage. Ethernet is the future!
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The 13" models were never really prone to GPU failures. The early 2011s are just a bit slower than the late 2011s. If you stick a SSD in it with a 16 GB RAM upgrade then they really shine in terms of performance. Keep in mind that they are the second to last model to run OS X 10.6 Snow Leopard!
The late-2011 works with the early-2011 restore disks to get Snow Leopard back on it. I borrowed some from work to banish Lion off mine when I bought it.
You can also install 10.6 via TDM from an older Mac. Once it gets updated to 10.6.7 (I think) all the drivers are there to allow it to boot natively.