I play a spellfire wielder in a campaign. We're at 2nd level. It's a pain in the butt to recharge levels, I'm telling you. I have 20 con, with 15 spellfire levels stored. True, I could do 15d6 damage, but then, if I missed, I'm outta luck. I'm pretty much just going to use it as a compliment to my Clerical spellcasting until I get spellfire wielder, at which point I buy lots of wands of light and start using it a lot. It's not REALLY overpowered till 5th level fo Spellfire wielder where you get drain permanent item. Just buy 10-20 Quaal's Feather Token (I forgot which one it was, but the cheapest is 50 gp for 12 caster level) and drain em whenever you need more energy. And if you're using 3e, it's even easier, with dull grey ioun stones (25 gp, 12 caster level).