I like using Inbox and it seems like this Little part of Gmail is Getting more steam in it's system.. And is getting bigger yea.!
Here is more on Inbox Follow to Droid Life for more info:
I got an early invite months ago, but never found it to be a Gmail replacement for my needs. I don't email much nor do I receive many emails. My issue was with the archiving instead of deletion. I still have 10 invites. LOL