It also pays to note that manufacturers sometimes (and even more so these days) use custom components that you wont be able to use on anything other than boards of the same series, if at all.
When it comes to newer hardware like you're talking about, for me personally, unless it's the exact same chip being swapped, it all comes down to if it's worth the time and effort to attempt the repair. If I'm not 100% sure based on the info I can find in the Google machine that it can work, I don't bother. I don't want to waste time or possibly cause more damage.
On older hardware, what I work on most often, it's much easier becasue much of it is relatively well documented. On newer hardware, that's often not the case. Again, if I'm not completely certain, I don't attempt it.