All mudflaps are pretty similar. What separates them is mostly the quality of the amplifier and the fittings. Some don't come with a power supply so you have to use a phone charger or plug into a USB port that can power it. You get no more than you pay for.
In any case, with a title such as this thread has, mudflaps are mostly off the table.
I expect that the various sellers of mudflaps are trying to clear their inventories before some of the larger markets start seeing VHF channels as a result of the repack combined with the addition of ATSC 3.0 broadcasts (since ATSC and ATSC 3.0 are fundamentally incompatible).