In the garage, I don't use a dimmer and they were perfectly fine and there is not any delay. I have a number of these in the house and have found that below a certain percentage on a regular dimmer - from 0 to about 30%, the lights will flicker slightly. The solution is to keep the dimmer above that or purchase an Electronic Low Voltage (ELV) type dimmer. A traditional dimmer is usually 'MLV' - they use a magnetic core and coil, (copper wire wrapped around the steel core) while the 'ELV' dimmers are solid state (electronic circuitry) and are designed for the low voltage that these lights draw
If you look closely in my first pic, in the upper left hand corner, I have a junction box mounted in the ceiling with three pull chains hanging down. I don't need all the lights to come on that often so I set it up when I turn the light switch on I usually only have one row of 3 lights that will come on - if I need more light, then I just switch the other rows on by one of the 3 pull chains