PCs are simly PCs
What matters most is
Certification ( For professional purposes )
Warranty ( On-Site / Carry In )
Build Quality
Certification = This is cornered by HP and Mac. Majority of certified systems for profesional content creation will either be a Mac Pro or HP Workstation. ( Which can also take weeks to deliver )
Assuming certification does not matter, what is next most important is
Warranty;
1. CARRY-IN or ON-SITE
For Desktops, if brand only has carry-in warranty, i feel might as well buy from SLS, coz no difference
Brands like Asus provide On-Site Service Calls + Premium Phone Support
2. If going to SLS
IMO, price should not be the number one factor. There are certain shops like Infinity / Fuwell, which charge a premium, yet will not shirk responsibility via 30day 1;1
Some shops also outsource to a back alley assembler.
3. Ability fix own components without voiding warranty.
That little warranty sticker covering an essential hole to open the case...
The rest is subjective. If you like a certain brand's looks, then no choice.
Also, Aftershock limits components so as to streamline support. Nothing wrong.
If you want your own comonents, thats what a DIY PC is for..
anyway check out this reddit post
https://www.reddit.com/r/singapore/comments/4pht35/issues_with_aftershock_desktop_customer_service/