If I use RGB LED lights, will this milky diffuser get rid of the bright spots?

Hi. In order to avoid spotting you will need an RGB LED strip with a very high density of LED chips, something like 120/m. This is because LEDAL03 is a very shallow profile and even with a milky diffuser it will not be enough to avoid spotting. An alternative would be to use LEDAL23 which is a deeper/large version of LEDAL03 and should provide spot free installation. Feel free to contact us at [email protected] for more information.