Hi All,
I booked a DL ticket yesterday, and on one leg I upgraded me and my companion. I did the "instant upgrade" where I booked the ticket with a phone agent who then immediately upgraded me using my miles.
However, when I checked this morning, no miles had been deducted, yet we're both seated in first class; with seat assignments.
We're booked in "RP" Class.

Any ideas why this happened; aka is this normal?

Also, on a side note, what is first class like on the A319 and MD90? Is it better or worse than UA domestic first?