Gameplay-wise it lives up as a worthwhile Valve-quality new entre in the Portal franchise. It felt really good to be playing high quality test chambers again and getting to see a few mechanics that were scrapped from Portal 2 fully realized was cool.

Narratively? Very disappointing. Almost a beat-for-beat retread of Portal 2 with weaker characters. It introduces cool ideas with lots of potential and doesn't really do anything with them, and then ends on a miserable anti-climax. Huge bummer that really soured this in my mind.

I still think it's worth your time if you're a fan of Portal, especially considering it's free.