Is there no point in having this much RAM with a normal upload speed?

So my computer came with 16GB of ram (i5, 3.1ghz btw) but I'm wondering if it's really necessary. My upload speed is a little above 4.3 MB/s and according to http://canihostaminecraftserver.com/, I can only run 13 players stably. Is this accurate or not? If so, will there be any advantage in having all this RAM? (like less lag when playing MC along with hosting the server)

Thanks in advance

 

That website is a load of bull...

You should be able to host at least 20 players if you keep the PC clutter free.
Dedicating the full ram will not make it better, just use 2gb and you will be good to go.

 

I have 12 GB of RAM and run CraftBukkit with 4 GB allocated to the Java heap. It works well with 15 players. I have an 8 Mbps upload.

Having 16 GB of RAM means you'll be able to use the computer for other things while the server is running.