With a big family, I think a big slow cooker is a must. Big one pot meals can be a life saver on a busy day. But personally I don't think you can call it a "one pot" meal if you have to first brown some of yourself in a separate pot on the stove.
That's what I love about this slow cooker - it truly lets you do one pot cooking, because the insert is metal and can go on the stove! So you can brown your meat or saute your veggies on the stove, and then just add in your other ingredients and drop it directly into the slow cooker to finish up. It's non stick and has a timer and it works like a charm for me every time.