Coin and concept is at infancy, I had no issue at all with dual miner, but I guess it depend on system and with which primary miner is used
Everyone who do not mine grin (on windows) or have ~2+ GB of ram free on GPU can run this miner as same time with no need for start/kill bat files and zero issue to primary miner hash
With GPU-z under sensor tab you can see Memory used from total ram (4,6,8,11GB)
win 7 you need to have 1.3gb free to not use --clear-dag and start-stop
windows 10 you need to have room for 2GB
Also due the number of miners and low reward, its profitable mostly for full rigs mining and not so match for one card alone
Also network is very slow in last 12h, one pow in 5-6h