I've used Micro Sol for around forty years, without problems. Sometimes, it may affect the acrylic clear coat, which might turn slightly cloudy, but this clears as it fully dries.
The Micro Sol is the decal softener, and Micro Set the setting agent, but they both seem the same to me, so I only use the 'Sol', especially as I have had problems with the 'Set' grabbing the decal too quickly, before accurate placement.