A filter-based instrument is likely to be more sensitive for detecting the Trp fluorescence than a monochromator-based instrument, all else being equal. The filters typically have wide bandpasses, which is why they are more sensitive, but they tend to have less spectral resolution than monochromators. With most filter-based instrument, you can measure changes in intensity, but not changes in peak emission wavelength. This measurement would be achievable with a monochromator-based instrument, however.

I think all fluorometers have both. Monochromator (diffraction grating) to generate monochromatic light and filter pass to control the exposure. But the question is on the benefit of using filter baser monochromator. Its always have better sensitivity.