Hello Danny,
From my personal experience, Smart-1 210 works fine with R80.X as management only (and peraphs SmartLog too) with its default RAM.
To me, the main problem was when SmartEvent was enabled, which gave some performance issues (specially with RAM). As Check Point recommends on R80.10 release notes:
If you want to execute Management, SmartLog and SmartEvent; definitely you should upgrade the RAM to 16 GB. Otherwise you can run only one of the three (without affecting performance).
This is the SKU for RAM upgrade: CPAC-RAM16GB-SM205/210
Regards.