Whether or not your Pi is up to the task will depend on a number of factors such as SSD speed, network connectivity, etc. As such, it's best to verify performance on a testnet first.
The best thing you can do is to set your Pi to run Pyrmont. If you have no trouble syncing and attesting on Pyrmont, your setup should be more than good enough for mainnet as well (Mainnet is expected to use fewer resources).
We've been running lots of PIs and NanoPCs 24/7 for 3 years and never got a hardware fail. It is easy (and cheap) to get redundancy of components (even spare PIs in different locations, more of this to come).— Ethereum on ARM (@EthereumOnARM) November 28, 2020
Although we don't expect a modern Pi to fail, we recommend buying a spare Pi, and enterprise grade SSD, on the off-chance it does; keep your original SD around, to make it easy for you to copy the image over.