Advice with filters for the Nikon d5100?

I found a kit from Hoya on amazon for $60 which includes the UV, Circular Polarizer and NDX8 filters, and I found an RM-72 Infrared filter from Hoya on amazon for $52. I would pretty much just be using them for experimentation, so is $110 really worth it? Or would cheaper Polaroid filters work just fine?

If by "cheaper" you mean linear polarizing filters, those are incompatible with the phase detect autofocus used by the D5100 and most DSLR's.

Hoya has developed a reputation based on the quality of their product. Polaroid has not. So if you perform an experiment and it doesn't go well, is it because of you or a poor product?