This one is our favorite iPhone X middle layer reballing stencil. We have tried many stencils for this challenging job and this is our pick, it is the one we use every day. It has a magnet assisted alignment mechanism and if you use it the same way we teach at Practical Board Repair School or in our YouTube videos you'll be able to have success in the essential skill of reballing the split board iPhone X.
We prefer to use it with our standard 138C iPad Rehab verified bismuth solder paste (sold separately) rather than the Glon paste.
Also note: For iPhone XS/Max middle layer, we use the stencil that is included with our XS/Max iSocket from QianLi.