I think Dawnblade's melee is great. Swift Strike is clearly the better of the two, but since both provide burn, both provide for the most basic 2-hit melee in the game for PvP. I like it especially when paired with Sunbracers because they take about half of your nade cooldown off, and with top-tree, you just throw constant long-lasting Solar nades and always have a Swift Strike active in encounters with large amounts of mobs. On Calus, you can throw 4(maybe 5 with cooldown mods) long-lasting Solar nades with the raid mods and Sunbracers. And if there's an O. Rigs Nightstalker constantly making orbs, much more. It's great if you're team lacks the damage to immediately 1-plate.