From a simple codex reader's perspective, I might add that those for the same price as those death company, you can actually have:
(105) 5 Assault Marines, flamer, jump packs
(75) Sanguinary Priest, jump pack
They now only lack the increased weapon skill and the extra benefit from having a chaplain (Which is normally an 100pt investment) but they don't have rage, and can also get meltaguns to deal with tanks on the turn they deep strike with descent of angels.
All analysis, no playesting behind this, but I think sanguinary priests are also valuable to more than 1 unit.