FYI
this one you linked http://www.trademe.co.nz/computers/desktops/no-monitor/auction-1224661972.htm vs this one on CL http://www.computerlounge.co.nz/components/componentview.asp?partid=28103
Processor
Intel Skylake Core i7 6700 vs Intel Skylake Core i5-6400 - about 18% faster overall
Ram
16GB vs 8GB - Double the ram but this isnt necessarily needed for what you are using it for.
Motherboard
Gigabyte GA-H110M-S2H vs Gigabyte GA-B150N-GSM Intel B150 Mini-ITX - only has 4 SATA3 slots, lacks M.2 support
Hard Drive
West Digital/ Seagate 2000GB SATA3 Hard Drive vs Western Digital Green 240GB 2.5" SATA3 SSD - ~3-4x slower but larger.
Graphics Card
Gigabyte Nvidia Gefore GT730 2G DDR3 vs Sapphire Radeon RX470 Nitro+ OC 4GB - 2GB less ram, and about 830% less performance. Also at least a couple of generations old and pretty much the lowest card in that series.
OS
None vs Windows 10
PSU
Not mentioned vs SilverStone Strider Series ST50F-ESB 500W - Likely a cheap low wattage unit
While it does have some things that may be a little better, overall it will be a slower system than the CL one