For what it's worth, I use a cut to fit AC filter over the top of the radiators on my B series. I did that with my G and K series skid steers as well. When the ac filter clogged, i could tell and would blow it out or toss it. It helped a lot by keeping "fluff" and debris out of the radiators. As a guy who mulched with an S330 and S300's for thousands of hours, the AC filter was a must have and kept me running a lot longer than I did before I discovered that using those helped. I've been doing it for almost 10 years and though I now have an M series skid and don't need the filter, I still use one on the toolcat.
I don't know much about the C, D, and F series TC but if they are pulling air through the radiators like the A and B, then I think the filters will help keep debris out.