^ Oh that's the episode, I was trying to remember which one it was. I think I've only seen it once or twice and the name wasn't familier.
How do you rate it?
Phew, good question

. I haven't seen it in quite a while. But back in the day, it was probably one of my favorite TNG episodes.
For one, I always liked Dr. Crusher as a character somehow so a Crusher-centric episode like this was very welcome. Secondly, I loved the sci-fi concept behind this episode where reality was constantly changing but the main character was the only one to actually perceive the change.
This opened up an interesting look at what perspective and perception really mean to a human being. You never see the whole picture, and it's extremely hard to see beyond what you have come to accept as reality.
Third, I guess I'm a sucker for episodes or movies that are about somebody being the last person in the world. I think the episode did a great job of capturing that feeling which isn't that easy to achieve. Crusher's feeling of loss is palpable and connects with the very down-to-earth reality of having to deal with losing people as you grow older.
There's quite a bit of technobabble involved, of course, and Wesley tends to be his annoying self. But as you can see from above, it's not what stuck in my mind first and foremost.
I'd certainly say it's a very good episode and worth watching. Though, again, it's been a while since I last saw it, and TNG as a whole hasn't aged too well for me (though I did enjoy both BOBW and AGT when I last re-watched them).