To put it in perspective I went to B&H's web site and sorted film listings to 120 film, black and white negative, speeds 100 and 125, then sorted to display least expensive to most expensive. Acros is still the least expensive at $3.89. Next is Delta 100 at $4.19, FP4+ at $4.25, Fomapan 100 (!) at $4.29, and most expensive is TMX at $4.50. Considering what a good film Acros is and the unique reciprocity failure characteristics, it's still a small bargain, but "small" in the sense that all these films are close enough in price, for most of us anyway, for price not to be much of a deciding factor. Use the one that you prefer.
I put the exclamation mark by the Foma because I'm surprised to see it more expensive than every other film except TMX. Of course it's available in the US from Freestyle in their house brand Arista EDU Ultra for $3.09, so I at least would never pay $4.29 for it just because the box said Foma.