There are big differences in prices when it comes to wattage of smart lights. For example, in Jan 2018, a MagicLight smart light which is 40W equivalent costs $19 plus taxes in Seattle, WA, USA. While same brand bulb which is 60W equivalent costs $31 plus taxes.
[Bonus read: Benefits of Smart Lights, if you have not read it already!]
I prefer buying 60W as that gives me a flexibility of dimming it to 40W equivalent whenever needed or according to my scene settings while having a 40W smart bulb cannot give you a flexibility of 60W when you would want. You will have to replace it with a 60W smart bulb.
However, due to cost and desire to have 60W equivalent, I switched from MagicLight to Lohas smart bulbs.
There are definitely pros and cons when you buy something branded like Philips vs. local bulbs such as Lohas. One major difference is the color setting. I tell my Google Assistant to set the light to Bottle Green and it sets it to very much like a blue. However, when I tell her to set smart light to Dark Green, she does the job perfectly. Maybe there is a problem in the software that Google received from Lohas but who knows and I don’t care as long as I can at least get some kind of green!
This is literally how my dog has grabbed my laptop as I am writing this post!