Which light to use??

My seedlings are currently 10 days old and pretty big.

I am using a Spider Farmer 100w non dimmable light, but I have just had a 300w dimmable mars hydro light arrive (FCE-3000) should I put that in as it covers more area? and use the dimmable feature to have it at say 30 percent? 40 percent? or carry on using the 100w until it enters veg?

Don't sweat the small stuff, both are capable of doing the job, if you're gonna finish under the nee light and u wanna get it set up then switch now, but i can't see it making much difference yet

just leave the little light for now then have the other one ready for your area. the one thing about dimming the light is that it changes the spectrum. If you had the light up already and it were a pain in the ass to move i would use it dimmed. If they are not getting enough light and stretching though id change it now and dim goodluck ! well just looked up the dimming and spectrum guess it doesnt matter as much with a quick search