Yeah so I had this issue with my Late 2011 MBP a few months ago now. I'm from the UK, but emigrated to NZ and only a few weeks in, the machine died. Since I wasn't in the country of purchase, I wasn't covered by consumer law in either country.
The local repair centre quoted me between $1500-$2000 NZD (!!!) for a logic board replacement and I already knew from the lengthy thread here (now much, much longer!) about the issues with replacements failing; it's a design fault, so there'd be little point replacing like-with-like. If I ever wanted to sell the machine on, I could hardly do so with a clear conscience knowing it was going to fail sooner rather than later.
Due to needing the machine for work at the time, I was forced to buy a Retina MBP to replace the 2011 model while I got the old one fixed. The old one had been upgraded to 16GB RAM, 960GB SSD; thus the absolute fastest highest end machine Apple make right now (since they are no longer user-upgradable - "pro" my arse!) was only capable of just barely exceeding that specification, CPU aside. 16GB RAM, 1TB SSD at huge cost. It does have a higher res screen, but glossy not antiglare; there's no CD drive; yes it's got a more efficient CPU and the battery lasts longer which is nice... But it looks like it's a lemon. A Thunderbolt dock that my 2011 machine worked with fine doesn't operate properly with the new machine and I've had countless mysterious lockups. Apple are now pointing the finger at the dock people, the dock people at Apple. Yet another hardware disaster. I won't be buying Apple again.
In the mean time I had a UK company (BGA Repairs, eBay, recommended from this thread) do the resoldering of the GPU with leaded solder, taking advantage of an upgrade to the 6770M while I was at it. Machine disassembly was very fiddly and I managed to damage a fan connector while I was doing it, but the UK company fixed that as well. The cost with shipping in NZ dollars has been about $400. Compare that to Apple's $1500-$2000 which wouldn't even properly fix the machine. The 2011 laptop is now reassembled and running cooler than before, which again is a damning indication of poor build quality in the original machine - the well-known and frankly inexcusable issue with thermal paste application in the factory.
I suppose it's time to go for many reasons. I've used the 2011 machine as the "fall guy" to test out Yosemite, and to be honest I can't see I'm going to miss Mac OS. iOS and OS X are both heading in visual directions I dislike strongly (the spidery, minuscule new font on these discussion forums is another example of poor choices), with a lot of usability issues from my perspective - that's a very personal thing though. The mounting iOS and OS X bug count isn't quite so subjective, however; and since Apple seem to now be exceeding Microsoft for one-off weirdo crashes and hiccups, I may as well save my money and go mainstream with some box shifter PC laptop. It might only last a year or two, but I'll be able to buy five of them for the price of one Macbook and each year's model will be better than the last.
A really sad tale all in all. I wonder if they'll realise they have a very serious hardware and software quality problem and rectify it before it's too late?