Think about other vegetables in your vegetable bin: old carrots, old celery, for example. They are floppy, not firm. Same is true of broccoli. Firmer is fresher! Any variety of broccoli should be firm and green (or green and purple) with no yellowing. (Well, there are some Chinese broccolis that have yellow flowers, but they're the exception. And even when the flowers are supposed to be yellow, the stalks should still be firm.)
This is what I've been assuming (and buying). As you say, like carrots. But I just got into an argument with someone who said that the freshest will bend. Then I thought maybe it's only firm because they pack it in ice when shipping it to the grocery store.
What's it like when you harvest it from the ground? Anyone grow fresh broccoli that can answer this?