Well the interference you spoke of was the first cheap one that came out as the cables were not correctly insulated which allowed some digital signal to leak and make a hum on certain radio freq but that was correct on all models. On the setup a digital ballast is better because...it outputs almost 30% more light, can save almost 15% per bill over a magnetic, it has instant start and no hardstart so it saves the life of your bulbs by almost double. The ballast run silent no hum to vibration so very stealth. It weights about 7lbs instead of 40 lbs like magnetics, its half the size so is eay to place and mount,it auto detcts bulbs so it will run mh and hps bulbs no switches or conversion bulbs like magnetic base and the ballast run cold you can hold it and not a bit of heat so no heat signature or heat given off to a grow room. Is that a good start why they are good.Now not sure which package HTG gave you but Im guessing a ballast,bulbs and a wing reflector? I am guessing but correct me that you bought an hps magnetic unit so it wont run mh bulbs unless you buy an exspensive conversion type bulb correct? So I could get you a 400 watt digital ballst, wing reflecter, and bulb if your in the US or Canada for right at $165 delivered with 3 year warranty on the ballast. I also can do 250 watt,600 watt,750 watt, 1000watt and LED lighting.Oh I assumed 110 current but can provide 220 if needed...lol side note I also have unlocked Iphone clones ,blackberry storms,black berry bolds and pretty much if you give me a model phone I can get it no contract new in box with 1 year warranty but thats a different topic lol oh and xbox 360 systems lol