I've never used a BGA unfortunately. My understanding is that BGA solder-balls come pre-attached to your chips in most cases. As long as you reflow-solder it o

I've never used a BGA unfortunately. My understanding is that BGA solder-balls come pre-attached to your chips in most cases. As long as you reflow-solder it on correctly on the 1st try, you're good. If you need to "fix" BGA, that's where things become very difficult for hobbyists. To do this, you need to unsolder the BGA with hot-air, lift it off, then "Reball" the BGA, which is equipment that likely hobbyists don't have. ------------ With regards to QFN or DFN vs BGA, I would expect BGA to be easier, as long as you've precisely made your soldermask to accept the correct sized solder-balls (which should be part of your chip's documentation). That is: BGA's hardest part is getting the board design just right. Especially because most BGAs require 4 or more layers before you can route all of the lines to them. In fact, the massive BGAs are physically impossible on anything less than 8 layer boards. ------------- Hobbyists won't have XRay equipment to see if the BGAs successfully worked either. So rework and quality-control are basically impossible. Your only hope is to "do it blind" and hope for the best. Which... is fine? Even BGA parts are relatively cheap. So build 3+ of your design at once. Have appropriate test-probes to take measurements during the "smoke test", and bam, you're good. One of those three tries is probably going to be successful.