Originally Posted by JakeTheBuckeye
My typical setup consists of a Capilene base layer, Patagonia's down sweater, and the Powder Bowl shell. If it is a warmer day, I swap the down for a fleece (or even just use the Capilene and a soft shell), or if it is an exceptionally cold day, I add the fleece to my standard setup. In response to your question, the down sweater makes an excellent mid layer. I have had a couple 3-in-1 systems from TNF and others, but I much prefer my current setup.
This. I like the layering system b/c of the flexibility it provides. I have some capilene and some heavier (for colder temps) stuff as underwear. I own a down sweater, a lighter merino thick sweater, a windstopper shell, a thick soft shell, and a Gore ProShell. I mix-and-match depending on the temps. High temps = windstopper shell; a little colder throw in the sweater, colder still = down + windstopper; cold + snow = down + thick softshell, full on blizzard = layering + ProShell.
The flexibility to adjust with the weather is why I like the layering.
My first jacket was a Columbia with a zip-in fleece liner. It just didn't work as well in as many conditions as what I've built up. It was also much bulkier than what I can put together with the above (with the exception of multiple-layers under the Proshell...and then I think the Columbia wouldn't have been warm enough for those conditions). I will say this: the jackets I've accumlated was a boat-load more $$$ than that Columbia jacket, so it should work better in more conditions.