[H] 8GB RAM on NAS

[Winterlight]

I am planning a Synology DS916+  4 bay purchase. This is for media 
streaming/recording,  security cameras, data backup on a Single User 
LAN. I have a choice of 2GB RAM or 8GB of Ram at a difference of 
$100. Do I need 8GB or RAM on a single user network...maybe for 4K in 
the future?...  Or not.