Shard O'Glase said:And quite frankly the presitge class sucks, so don't take it.
I disagree.
If you plan on taking the Channeler prestige class, from first level, you can do some amazing things. A Rogue/Channeler can be very effective, especially at higher levels -- if you get in position to pull off frequent sneak attacks, that spellfire energy can be made to go a loooong way.
I can post the stats for a Rogue(11)/Channeler(10) I made for an Epic Campaign I ended up not playing in after all, if folks are interested. For now, suffice to say: 1d6 spellfire blasts + reliably usable 5d6 (?6d6?) sneak damage against anything vulnerable to criticals ... three times per round ... as a standard action. 28 CON, giving nearly 400hp (294 of them = CON bonus), and, a 140 maximum Spellfire pool. Potentially very ugly.

And 20 wands (10 Detect Magic and 10 Light), 50 charges each, for 1000 charges ... each drainable for 1 point of spellfire pool, between encounters. Not terribly expensive at that level, either.
So, I'd say the Spellfire Channeler PrC is useful, if you plan for it, and know how you will use the abilities gained.