All I have are the stock proline foams. They aren't bad, but I was remembering how trashed the last foams got after two years of running my maxx series mashers. Is it worth ordering them? Any harder 40 series foams people know of?
Only problem with most of the molded foams is that they are for low profile tires, which the Mashers are not. You may end up with some dead air space in there as the foam won't completely fill the tire. You may want to try the losi 2-stage foams (LOSB7222), they are firm with a soft layer near the tread, I really like em. I think the standard losi ones (LOSB7221) are pretty firm if that's what you are looking for.
i bought a set of those yellow ofna foams for my losi bolt ons and they were too small. i believe the mashers are about the same size as my bolt ons which is just about 6 inches tall.
i went and bought the losi 2 stage foams, and they fit well.