Going cheap on an HPS setup?

[Walter Bellhaven]

I want to get a 100W HPS setup going, and it looks like I have two options. Here's a ballast for $18, and a bulb for $6:

100 Watt High Pressure Sodium
100 watt HID High Pressure Sodium Bulbs: 1000Bulbs.com

And here's a ballast for $50 and a bulb for $17:

100W HPS Ballast Kit S54 Quad Tap - ProLighting.com
LU100/MED|C100S54/M|100W HPS Bulb Medium Base Clear - ProLighting.com

WTF?? Which one should I get? I mean, how big could the difference possibly be? And yeah, I definately want to go cheap!

Walter Bellhaven Reviewed by Walter Bellhaven on 07-17-2008. Going cheap on an HPS setup? I want to get a 100W HPS setup going, and it looks like I have two options. Here's a ballast for $18, and a bulb for $6: 100 Watt High Pressure Sodium 100 watt HID High Pressure Sodium Bulbs: 1000Bulbs.com And here's a ballast for $50 and a bulb for $17: 100W HPS Ballast Kit S54 Quad Tap - ProLighting.com LU100/MED|C100S54/M|100W HPS Bulb Medium Base Clear - ProLighting.com Rating: 5