Yes, I have stackable trays so the worms migrate up.
Yes, the temps are fairly constant: the worm habitat is in the carport. The carport has a 4-hour-rated firewall on the west side (property line), and the habitat is within a foot of the firewall and about four feet in from the south (open) side. The entire habitat is covered with an old army blanket to smoothe out the temperature changes, both up and down. The worms are always in the shade.
These worms have survived record high temps (103 deg F) and record low temps (22 deg F) since May 2008 in their carport location. I added the blanket when the record low temps were forecast in December 2008, and the worms rewarded me with mass survival.
I assume that the worms experience an entire life cycle, including death; however, the others have never been put off by or indeed even allowed me to find their dead comrades. There is an abundance of cocoons.
I've been separating vegetable matter and recyclables / returnables from my actual garbage in the kitchen since (ahem...) before Earth Day made it to Atlanta. (I was 16 when I left my parents' home forever.) It is such a habitual way of life--veggie waste goes here, paper over there, cans in the bucket, etc.--that I can prove that it saves me both time and money. Money b/c of the smaller size garbage can and the smaller fee paid to the city waste hauler; time b/c all the separation takes place at the source and not afterwards.
I shred newspapers whenever I think about it, usually during the winter rains, and I fill a big yard bag with shredded newspaper. This lasts for at least a year, often longer, as worm bedding. Not a bad investment of 30 or 40 minutes!
My "15 minute per weekend" guess is really on the high side. It allows for my walking downstairs from the kitchen (14 stairs; I have a very bad right knee), walking out to the carport, taking the blanket off the worm habitat, taking the lid off, ooh-ing and aah-ing at my little invertebrates and aren't you working hard today!, burying the food/veggie scraps in the current location, putting the lid back on, etc., and going back up into the house. I can stretch out the 15 minutes if I want some social time with the worms
but, really, they're not much in the way of conversationalists!
For someone who can walk normally (like DH), this whole process takes 6 or 7 minutes max. And it takes place once a week.
When I'm not feeling well (pain attacks and/or migraine), I stretch out the feeding intervals to every other weekend, so we can cut the time down by a factor of 2. Me: 7 minutes/weekend; DH: 3 minutes/weekend.
And don't forget to check out the possibility of purchasing a discount or subsidized worm bin from your municipality, county, or private solid-waste provider. Many, many jurisdictions in North America offer these "deals" due to legal requirements that they reduce their landfill contributions posthaste.