Hi Tracy,
The Eballast will fire Iwasaki bulbs, no problem. You do want to start with a brand new bulb though, they don't seem to fire bulbs that were burned on a regular ballast first.
Eballast seems to be a very reliable ballast, seems to fire most brand bulbs and no flicker or hum. It usually will save you about 20% on electric.
Icecap Halide does have a few problems, but most are very good. I run several icecaps at the shop, i do have one 250 that doesn't always fire the Iwasaki bulb first time. Icecap does have a nice 3 year warranty and always fast on fixing any ballasts.
With IceCap, you do get a pretty good boost in performance, it's brighter then a standard ballast or eballast and is a much lighter ballast. Icecap is 1.5 pounds, Eballast about 9 pounds, standard about 15 pounds. So you do gain a few things going with Icecap.
I think you'll see more and more improvements in electronic ballasts soon. PFO now makes a 150watt and 175watt electronic ballast. IceCap has been some 250watt hqi work. We have a new LN Halide ballast in 175 and 250watt that runs any bulb in it's wattage, even hqi double end bulbs. So i see things just getting better and better for our hobby when it comes to lighting.
jason