Backup plane for checkride: Can it be a different model?
I came to the same conclusion as you, I don't see anything keeping you from going. You meet the requirements of 61.107 and 61.109, you have recent experience in both aircraft, and as far as make and model, they're both PA-28's. That's like going from a 172B to a 172S: it's the same make and model, Piper just makes it a little less obvious with their nickname and number combinations. If you had trained in a Warrior 160 and an Arrow, it would be a bit different, but only as far as requiring an additional endorsement.