I have it running in different environments (two of them at an enterprise level, one with more than 100 clients). They all run on Raspberry Pi hardware in various revisions. They never failed so far, so I wouldn't bother too much.
A clever idea might be to set up two independent Pi-hole's and (two distinct devices in the same network) and set up those two IPs as "primary" and "secondary" servers. All devices should be able to resolve domains, even if one of them fails for some reason. The costs of an extra device (with the excellent NanoPi NEO it is only $8) should perfectly balance with the extra reassurance you have for your holidays.
P.S: This is the post I referred to, just n case you haven't had found it already