Complex sentence: Superstardom perpetually evaded them, though, perhaps in part because of their frequent line-up changes, but despite that their next album, "Hellbound Train" (1972) was a Top 40 album for them in the US.
Split into simpler sentences: Superstardom perpetually evaded them, though, perhaps in part because of their frequent line-up changes. Despite that their next album, "Hellbound Train" (1972) was a Top 40 album for them in the US.