I’ve been running a full node for Bitcoin (and Litecoin) for a couple of days now. It guarantees that I’ll always be able to make transactions since I can connect to the network through my own computer. That’s basically the idea of it. It took a while to sync the thing, but that was until I found out about this trick: to put the chainstate directory on a SSD and create symlink to it from the external drive to where I sync the blockchain. The Bitcoin Wiki has more detailed information.