The part itself is a perfectly good replacement. When I bought my N3DSXL, the touchscreen was completely broken, so I don't have any OEM experience to compare it to, but the replacement touchscreen worked right away without needing calibration, and the sensitivity works exactly like I would expect it to. Notes on the installation process below:
As an intermediate tinkerer, I found putting this touch screen in fairly quick and easy to do. No soldering required, but of course there are LOTS of ribbon cables (this is a post-Gameboy Advance Nintendo handheld after all), so some patience and caution are needed. The hardest part was removing the main circle pad simply because the guide I was following wasn't very clear and most videos I could find didn't do a great job showing how to remove it. You don't need to remove the "thumbstick" portion of the circle pad for this repair; You just need to unscrew the bottom housing from the PCB side of the device, undo the ribbon cable (It's a wonky ZIF connector, of course) and then yank the bottom portion of the circle pad straight up. (DO NOT do what I did: trying to pull the plastic nub off of the circle pad from the screen side of the device. This will break your plastic nub. I super-glued it back together and all is well, but I thought I'd give some warning ahead of time.)
Aside from that, it's a simple matter of disassembling the New 3DS XL piece by piece, then heating and separating the touchscreen once you get to it. I would recommend getting a roll of some good double-sided tape, since you would have to be much more careful to preserve the adhesives otherwise.