I had never used a waist coiled rope until foiling but are a big fan. Everyone has their own preferences but for me I find it never gets in the way especially when having to get out of the water and walk back around to the point after long rides. I have used it in overhead waves many times without any issues - never sprung back at me but always seems to be close by to get on board quickly. Sometimes when I have swapped boards with a mate with a standard leg rope, I immediately notice the drag in the water and keep trying to make sure it doesn't get caught on the foil. I have only had mine caught on the foil a handful of times.
I did notice after about 5 mths that the 10ft (7mm thick) coil does start to stretch and lose some of the tight coil which I think also contributed to it breaking at the belt attachment ( probably related to losing its spring effect). I bought mine from EBay for about $27 from China which seems to supply many of the Amazon and surf brands.
www.ebay.com.au/itm/Surfboard-Surfing-Training-Waist-Rope-SUP-Leash-Stationary-Cord-for-Beginner/303357915871 I'm sure One Ocean Sports has a higher quality one and this is a consideration for the level of investment in foiling.