+1 for the Lee Ram prime. Simple, reliable, works on any single stage press.
My favourite is the Hornady hand prime. Works without engaging a thumb, but if there is pain in your hand, there are other tools.
The RCBS APS press mounted priming tool was my biggest disappointment. To get it to cycle reliably, I had to make a new primer seating rod to the max diameter that the mechanism can accomodate. The existing one is a bit undersize and wobbles, causing the jams. From the design, it looks like everyone is having the same problem with it.
I have a primer feeding tube setup on my Redding single stage. No need to handle primers except for filling the priming tube. Same primer feed principle as the Hornady progressive press.