Works wonderfully and is not that labor intensive. I did the greenhouse thing (no heating pad) and while it works, I couldn't keep a good consistant temperature. Potawie mentioned in a thread on here about placing the bags on top of your fluoros in you have them, making sure to keep them off of the ballast(?) I think....a small 6-8" section that is really hot. I did that and got good cosistant germination.
I had tons of sprouts and germinating seeds scattered throughout a couple different greenhouse cells and whatnot. I found out the easiest thing to do was to get a 72 cell tray (if you have that many or close to that many) and go ahead and fill it with whatever growing medium you're going to use for the seedlings (not growing plants, but SEEDLINGS) and fill all the cells up that you think you will need. Once a day (after I got home from work, got the kids fed and in bed, etc) I hold the bags with the coffee filters to the light and if there are seeds that have their little tails growing out, Id take out of the baggy and used a decking screw with 3/8" marked on it, and poked a hole to the mark, dropped the seed in tail down, gently filled/covered the hole and marked it. Within a day or two it would be popped out of the grow medium.
For the most part, since I've went to putting the baggies on the lights, I get atleast 95% germination, 100% on some seeds. I had some that weren't always a consistant temperature before I read Potawie's post about placing on the top of the fluoro lights that molded and rotted, but havent had that problem since placing on a consistant heat source.
Probably how I will start all of my seed next year.
METHOD: Coffee filter, dipped in warm water, wring it out, but still plenty wet, just enough so it doesn't drip, spring seeds on one half of it, fold in half, then fold in half again, place in baggy, press air out of baggy and seal, place on consistant heat source and check daily.