The Samsung Galaxy Note 9 originally features a 6.4-inch Super AMOLED display. However, if you're referring to an In-Cell WF (Waterfall) LCD replacement, here’s a comparison between the original and the aftermarket screen:

Original Note 9 Display

• Type: Super AMOLED
• Size: 6.4 inches
• Resolution: 2960 × 1440 (Quad HD+)
• Pixel Density: ~516 PPI
• HDR Support: HDR10
• Curved Edges: Yes (Infinity Display)
• Always-On Display: Supported
• Contrast & Colors: Deep blacks, vibrant colors, and excellent brightness

In-Cell WF (Waterfall) LCD Replacement

• In-Cell LCD Technology: Integrates the touch and display layers, making the screen thinner.
• WF (Waterfall) Design: Tries to replicate the curved edges of the original screen.
• Lower Contrast & Color Accuracy: Colors appear less vibrant, and blacks look more grayish compared to AMOLED.
• No Always-On Display: LCDs can’t turn off individual pixels, so this feature won't function as well.
• Lower Power Efficiency: Consumes more battery than AMOLED screens.
• More Affordable: Cheaper than original AMOLED replacements but sacrifices display quality.

If you're looking for a replacement, In-Cell WF LCD screens are a budget option but lower in quality than the original AMOLED. Let me know if you need help choosing the best replacement!