[Yana]

I am fortunate in having more than one greenhouse (two aluminium ones and one wooden greenhouse/shed combo) and during the summer the sun is high enough in the sky not to be a problem and the overnight temperatures aren't that different in the greenhouses.
This is the first winter for the wooden greenhouse/shed combo and I've noticed that the low sun means that the greenhouse bit gets the sun but not as much as the aluminium ones and the wooden greenhouse retains the warmth overnight better than the aluminium ones.
My question is this .....
I'm growing salad leaves, pak choi, and the like in wooden crates lined with black plastic and drainage holes punched in the plastic / drilled in the bottom of the crates. Would the crates be better off in a sunnier greenhouse that is colder overnight or a less sunny greenhouse that keeps warmer overnight??
Please don't suggest moving the crates morning and evening between greenhouses as they are quite heavy. 

[jrko]

I'd take sunlight.  Drives the growth.  That's as long as the temp drop at night isn't cataclysmic 

[brokenglass]

Large temperature difference day/night shock plants and cause them distress.

[sunshineband]

I'd go for the sunshine and fleece the crates at night