I use real packs and inserts if I'm hiking far, skiing, cycling, or climbing a peak.
But for around town or shorter walks my Lowepro Flipside 300 is pretty good for a FF body and 3 lenses (in my case Pentax K-1, 15-30/2.8, 24-70/2.8, 70-200/2.8 ). It was pretty inexpensive and my main criticism is the tripod holder. Just not well designed and the tripod will flop when you walk.
I'd like to replace it with something that handles a tripod better but I'm not in a rush. Without a tripod it's great and can't be opened from the back so it's good in urban situations like subways.
I also have a couple of Crumpler shoulder bags for around town with a smaller kit (like a 3 prime FF or crop kit). The Four Million Dollar Home is good for the minimal kit or the Six Million Dollar Home if I need to bring a little more.