I used this as a taru BRD from 18-32. "Taru" means I needed the extra damage from Enfire, and "Bard" means I rarely melee and wanted to make every swat count.
Only downside is that the item cannot be recharged, nor can it be AH'd once you have used ANY charges. (I knew this going in, mind you.)
You can continue using a "used up" Vulcan Sword as, in effect, a Flame Sword (i.e., it will add fire damage about one hit in 4-5). Or you can send it to someone you know who wants a Flame Sword ... or you can drop it.
What I wish is that the sword actually BECAME a Flame Sword after the charges were used up; that's what it functions as anyway, plus, as a Flame Sword, YOU COULD SELL IT on AH.