How heavy impact does this have on the frames?
It shouldn´t be worse than performance with reflection profiles of other aircrafts. You can test it out yourself, just uninstall it if the frames are too bad (click "Restore") in case you really have a old PC. I didn´t feel too much impact on the frames but my sim is also running on a hight-end rig, however you usually shouldn´t have any problems with Tomatoshade reflections
Aerosoft CRJ700/900 Tomatoshade Reflection Profiles
in Aerosoft CRJ liveries
It shouldn´t be worse than performance with reflection profiles of other aircrafts. You can test it out yourself, just uninstall it if the frames are too bad (click "Restore") in case you really have a old PC. I didn´t feel too much impact on the frames but my sim is also running on a hight-end rig, however you usually shouldn´t have any problems with Tomatoshade reflections