Modern high-density MLC flash suffers from read disturbance, i.e. each time you read the data, there's a small chance it will become corrupted. The controller in the SSD deals with this (using ECC techniques, a bit like how CD players can recover from small scratches), and rewrites the correct version, but it damages performance for read-intensive uses, and ultimately reduces the lifetime of the device.

But you needn't worry about this for Empeg purposes: it isn't a read-intensive use. Even booting the player is only a few megabytes' worth of reading, and reading the music data during playback is a mere dribble compared to what the author of that page was thinking of: booting Windows XP and having a pagefile on flash. So MLC will be fine.

FWIW, SLC stands for "single-level cell", meaning that each tiny capacitor-like thing in the flash stores either a zero or a one; MLC is "multi-level cell", in which the tiny capacitor is charged to one of four, or even sixteen, different voltages, to store two or four bits in the same cell. Quite frankly, it's amazing that it works at all.

Peter