The card I currently own is Thank You Preferred (I downgraded from Prestige years ago to avoid the annual fee).
There is no annual fee and I cannot transfer points to airlines with Preferred. I just keep the card for the purpose of having a longer average credit use. I have about 1000 unused points that I accrued when I had Prestige.
So I don't see any significant downside to converting to Rewards +. The upside (small) is 10% points back and rounding up to nearest 10 points on purchases.
I don't really use the card much at all so it doesn't make a lot of difference to me, but since they offer the switch I was wondering if any of you can see a downside (or significant upside) to accepting.
Thanks.