First of all keep in mind a really good scented candle, is not meant to be burned for hours.
They are made to last for days even while unlit after use.
For example a 20 hour candle, if burned correctly, you burn for 15 to 20 minutes, Blow it out and it will be fragrant for to 5 days usually more. .
So this candle can last for a very long time.
A 40 to 60 hour candle can last for a year..
I guess you can tell I have spent a lot of time around candle. It was one of the products I used to purchase and sell at the upscale store I worked for.
Trapp
AROMATIQUE
Votivo
Diptyque
These are all great candles. You may pay a bit more, but they will last for a very long time.
If you just love lit candles. Purchase good candles that are not scented, but only use your scented candles as needed. This was they will last a lot longer.