I've had experience with this twice. As for the replacement they offer you, it's completely up to which airport office you're dealing with.

1. One airport I had try to pull a fast one on me and just give me a replacement on site (as you have seen they are not the best) and call the claim closed. I refused and they initially requested me a check for a partial refund (something like 40 or 60%). Online I submitted pictures (Away bag that was crushed) and receipt. I was called a few days later stating that DL would replace the full value of the bag. Got check in mail. Bag was over a year old.

2. Another airport gave me a replacement bag without fuss but also helped file a claim for me, making it explicit that the claim was not closed if I accepted the replacement they gave me. I submitted pictures and receipt. I got an email a few weeks later saying that they will cover full cost of bag and got check in mail. Bag was just under or around a year old.

BTW OP, I felt like DL did me a favor when my Away was crushed. I didn't really like it after using a few times and never replaced it - got something different I much more prefer, but each to their own.