I have been at Czech for 6 months. I started with Who is She and am now going over it again. It is a real pleasure to see the words that I have moved to known, lightly underlined, and to find the odd word and phrase that I need to LingQ and learn now. It is a delight to go over the short list of LingQs in Flash Cards, a much shorter list than I normally have to deal with in the longer lessons that I mostly study today. It helps to consolidate some of the basic phrases and structures.

Does anyone else like going over the beginner material every now and again, even though they have progressed quite a bit beyond that level already?

Yes, often go back over old material. It's one of the most encouraging things to find that a lesson/text/audio that once seemed so opaque and difficult has become so much easier.

I remember telling myself that one day I'd be able to listen through those lessons without reading at the same time, and would understand everything as it was spoken. I should celebrate.

Absolutely, both for the reasons each of you (steve and maths) gives as well as a couple more reasons.

I download audio from longer LingQ lessons and other sources and burn them to a CD. Then I listen to the CDs in my car. Because I can't devote 100% of my attention to trying to understand difficult audio while driving, I listen to things that I've heard before.

As a bonus, from time to time, I discover that I like some pieces better the second (or third or fourth) time around, simply because they become easier for me to understand.

Sometimes, too, audio that I've heard before makes a nice filler to listen to while I do some short and mindless task like making coffee.

Short answer - yes, I've gone over Eating out and Who is she a couple of times ad nauseam (a few of my languages are now in hibernation).

Yes, I like returning to old content. It's nice to notice that what was once difficult has become easy, or at least less difficult. It's a real confidence booster.