MSI have had a 'warranty void if removed' sticker under their machines for years. Check before you buy as it can make upgrading painful. Forget about spindle drives, get a smaller SSD and just use an external drive if you have to. Loading a spindle drive just chews power, slows everything down, and makes noise and heat. They are the suck. Higher res screens require more powerful GFX cards due to the higher resolution. Think carefully about the 4k screen if you're only getting a low end GPU. Get a low latency wireless network card that supports the highest wireless range you can get. There's no point limiting your new machine to last years bandwidth. Think about a game controller to save your keyboard from being mashed. Replacing a laptop keyboard = expensive. Buy a decent mouse as well, SteelSeries and Razor make some great units. Lastly, think about the life cycle of your laptop : they do not last forever so work out when you'll likely want/need to sell it and buy a new one. You want to do that while it's still worth something. You also don't want to be stuck with a high end laptop thats out of warranty which developes a problem. Selling it while it's still valuable means your new machine costs less.
Dell Home, via its Member Purchase Program, offers its Dell 15.6" Laptop Gaming Backpack in Black/Red for $28.49 with free shipping. That's tied with our expired mention from four days ago as the lowest price we've seen for this bag. (It's the best deal we could find now by $20.) It accommodates laptops with up to 15.6" screens and features a shock-absorbent EVA molded front shield, adjustable shoulder straps, and a deployable rain cover.