Hello!
I'd like to move my gaming community from PHPBB to NodeBB. I'm somewhat disappointed about the improvements of PHPBB the last few years, and would like to simplify a lot of things for the people that register to the forums.
To give an idea of the magnitude of my community forum, I've included the PHPBB forum stats. (Please do not hurt me for not updating my PHPBB forum :()

In our PHPBB forum the shoutbox is relatively active (I guess about 2 messages per hour on average, with peaks of 20 per hour)
I'm planning to deploy the NodeBB website to a VPS with 1GB of RAM and 1 vCore. Also, the hard drive is not an SSD. Currently the virtualization is OpenVZ, but I'm planning to move to a new KVM VPS soon (with SSD). I want to host the database (redis/mongo) and the website on the same VPS. Do you think the server will be sufficiently performant on this hosting plan? Or do I risk getting a lot of 503 error messages when it's in use?
Also: What database should I choose? Redis is certainly more performant, but I'm afraid that it gets out of memory very soon. What database size can I expect? Will MongoDB be a safer choice?
Can someone advise me about these problems? I can solve other problems (migrating, configuring etc.) for myself 