Electronic ballasts perform better in every respect although the initial cost is a little higher. Possibly only a few dollars now between the budget electronic ballasts and a magnetic ballast. There are very few instances where you should consider a magnetic ballast.

"My friend want to buy a new economical ballast and reflector. I think electronic ballast is better."
Unless you are talking about regular fluorescent lights, there are no economical electronic ballasts. They are all expensive.

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