I had blotches. They were only ever visible when the entire screen was dark. Did anyone seriously care about this? They didn't affect the picture, which remains to this day a ludicrously beautiful and high-contrast one. The screen was always one of Vita's strengths. Having had a Vita I'd be all for OLED in the NX so long as it's affordable.
Blotches were only part of the problem. The biggest issues were:
1) Poor calibration, resulting in gaudy oversaturated colours. The IPS panel in Vita-2000 is well calibrated, and only shows saturation where it's necessary (like in Persona 4 Dancing).
The white point was also way off, which gave the screen this unnatural blue glow, as whites would appear blue-ish.
2) Burn in. Some users had the web browser menu bars burned into their screen, others had game HUDs.
3) very low max brightness. Peaks at 117cdm2, when IPS LCDs were reaching 600cdm2. This made it pretty unusable outdoors.
4) Mura/grain, which renders solid colours as grainy canvases, which is quite noticeable and distracting.
5) Power consumption. Vita-2000 gets about 2 hours more battery life out of a charge. OLED's strengths were squandered with Vita, as the OS and games aren't designed around black UIs or environments where the pixels are turned off. The best use of OLED to date would probably be Apple's watchOS, where the interface is pushed up against the edge of the screen, and the bezels of the watch act as the interface margin.
6) It's covered in greasy plastic. The Vita-2000's LCD is covered in oleophobic glass, which feels much better to the thumb, but also means fingerprints are never a problem. Every time I pull my Vita-2000 out of my pocket the screen is spotless. Meanwhile my Vita-1000 was always covered in distracting fingerprint oil stains. The plastic was also uneven.
7) Limited lifespan. Vita's OLED uses an RGB stripe, so it has a full amount of red, green and blue subpixels. While this is better than an OLED "PenTile" subpixel matrix, which would result in a lower perceived resolution, it means that the image quality degrades over time.
Blue subpixels in OLED displays degrade faster than the others, which results in even worse colour reproduction over the lifespan of the device (Samsung estimated degradation to occur after 18 months of daily use). So a screen that already displays stupidly off colours gets worse over time.
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Modern OLED displays have overcome a lot of these problems (1, 3 and 5, 7 is fixed using a PenTile subpixel matrix) but Vita's is pretty terrible by today's standards, and especially by the standards of the LCD model. The only real benefit to the Vita-1000's display is better response times, as the deep blacks are wasted since few games and apps show blacks.
