It's a collection of self-contained columns gathered together. They're all over the place in subject so if you went looking much more likely to find something specifically to draw you in. Also you can just skip ones you're not into without losing the overall picture like in GEB.

Different kind of book but similar explorations. I'd also say overall more enjoyable unless you're specifically into the thesis of GEB.

I Am a Strange Loop is for sure the least technical of the three but it's best if you read it last since it's a very emotional and touching denouement to the other two books.

You can read GEB or MT in any order, perhaps MT might be more approachable to start with since while it is quite technical, it's a series of articles that can be read independently of one another and each article has a bit of an aha moment, as opposed to GEB which is one loooong marathon where the aha moment is absolutely enormous, but requires a great deal of preparation.

> How does it compare to I Am A Strange Loop?

Don't know, haven't read it. But Metamagical Themas is a considerably easier ride than GEB, as it is made up of (mostly) independent articles.