Ott light differences

Is there a difference between the illumination of the ott table lamps? I want to get one but prices range from $16.99 on Amazon to $109.99 at JoAnn’s. Is there a reason other than profit for whoever’s selling it?

U mean like the different bulb watts?

I’m wondering if there’s any big difference in the lamps themselves. The ones I looked at were all 15-20 watts. Which wattage is the best?

Walmart has 24 watt replacement bulbs for $16.70. You can buy them online. Target has 27 watt ott floor lamps starting at $39.99.