i don't get what citronick is saying about "better heat control" but risers are imoprtant to make space between hot gpus, the closer they are together the hotter they get..
quality risers are good, most of my risers from late 2013 are still going strong.
Avoid the molex powered risers or any of the v1 to v5 risers.
Why avoid Molex - the connectors can EASILY handle the needed 75 watts (the actual connectors are rated for about 150 watts IIRC) as long as the WIRING is beefy enough.
Avoid SATA definitely, those connectors aren't rated for more than about 45 watts and WON'T handle the load.
to rslx - if you're willing to wait, your best choice is to buy from the manufacturer(s) direct.
One of my China suppliers shared with me that the worst riser power cables are molex and sata because during the mining boom a lot of back-alley small shops producing sub standard risers and M2 adapters.
If you go to Aliexpress, the good premium risers usually around 6-8$ bucks each. But now you can get 4-5$ each with poor quality molex and cable build.
Even the sata type has 2 versions - those that are "clamped" together usually has very high failure rate.
Those original powered risers with molex circa 2013-14 were probably the best you can get because the molex pins and cables meets/exceeds the standard.
I wonder what price power usb risers circa 2013-2014?