I'm a Ball lightning guy. Chak has its shining moments though...it certainly is faster then BL, but its limited in smaller spaces where BL could shine. I know some people don't like the "slowness" of BL, but if you've ever played a meteorb/frozen orb sorc in D2, you'll know what I mean when I say that the slowness can actually be very nice tactically if you take advantage of it. I can cast my BL to hit mobs while im running/circling/vaulting that Chak would miss completely due to mob pathing, delay in movement, etc.
to me they are both tools in a box and both should be used...but I couldn't choose both on the poll. so BL edges out Chak simply due to flexibility.