"Quantaray" is the "house brand" of Ritz Photo. You don't really know who the actual manufacturer is. Sigma are reported to make some Quantaray lenses, but I don't know about their filters. The lenses aren't particualrly good and are generally built to a lower quality level than normal Sigma lenses (which is why they may be cheaper).

If you get colored reflections from the filter, it's probably coated. Whether it's just coated, multicoated or super-multicoated is harder to tell.

It's probably fine. Take a few shots with and without the filter mounted. If you can't tell the difference, then it's OK!

Uncoated filters transmit about 91% of the incident light, with about 4.5% being lost by reflection at each surface.

The HMC filters typically transmit around 98% (less than 1% reflection per surface)

The Super HMC filters transmit around 99.7% (less than 0.15% reflection per surface)

The Pro 1D filters are similar to the super HMC filters optically, but have various other features like black edged glass and a matte black aluminum frame which are supposed to even further reduce the possibility of stray reflections.

For 99% of uses, I suspect the Super HMC and Pro 1D filters will give essentially the same results.