A lot of guitar compressors are based on variations of the classic Ross Compressor/MXR Dyna Comp circuitry, and the Ego is no exception - but it adds some extra features that greatly increase its versatility, most notably blend and tone knobs.
"It's great for adding a more 'singing' quality to clean (or dirty) leads"
You get a sustain control to effectively increase the amount of compression, and an attack knob, which tweaks the start of your note envelope to give it the sort of 'snap' that works so well for country picking.
But it's actually the blend knob that gives you loads more options for a natural but compressed sound, allowing some of your unprocessed tone through in parallel with the compressed. The tone knob can counteract any dulling and will add some sparkle if needed.
Adding a more 'singing' quality to clean (or dirty) leads, emphasising picking or smoothing levels for consistency - whatever you need a compressor for, this should deliver it for you.