As long as you are aware of the extra cost, going pre-built can be an option if you want a warranty or whatever.

My local computer store has a program called IPR.
That stands for Instant Product Replacement.
If the part goes for just about any reason, they replace it immediately.
That is not a repair or RMA process, but a brand new piece.
The same as you had originally, or if that is no longer available then the next piece up in that line.

IPR is not really that expensive, as warranties go.
But as with all insurance, it is not a loss for the company offering it.