the 1st link looks like a ballast kit only the pricee is avearge for a kit and the second is just the bulb in which case you could get a 250hps bulb cheaper than that if you look, the price is good but i've seen them for half that on this site.http://www.plantlightinghydroponics....ulb-p-124.html only 10 bucks there. i neither of your links included the reflector. this site here has the cheapest complete sets i've seen if that's what you're looking for http://californiahydro.stores.yahoo.net/index.html

i have no ties to any sites i linked other than having ordered from them in the past.