Best and Cheapest are two entirely different things. But I understand what your asking. I too like to get the best bang for my buck.
If your going to find out anything it's best to ask the people using the stuff your looking for. That way you can wade thru the good and bad more efficiently.
I just recently got into drones and once I got mine wanted something that I could keep everything related in one place. (The wife wanted me to do the same. LOL!)
I wanted something hard sided for protection while hauling it in my vehicle, and I as well plan too sometimes carry it on my motorcycle trips so wanted something that was robust but still not overly large while still holding everything that I have now that is related.
I ended up buying from ebay (My go-to store!) and got this one
.

It's ABS plastic with an aluminum frame.
I also discussed it with another member that had two of these and loved them.
I got mine and it does pretty much hold everything that I have except my tablet and the tablet holder that I made for it. I'll probably do some modifying in the case so that it will hold those as well. It's not a fault of the case however, just that I picked a bigger tablet and holder than most would.
I got it pretty quickly and total price was less than $40. I'm happy thus far with my purchase.