The pop-ups have been great and held up very well. They are by far the best pop-ups I have ever used. Buying the set of four has allowed our defense to expand our arsenal of pass rush drills. Other position groups like the DB's are putting them to work as well. We throw to the pop-up as if it is a receiver and the DB breaks on the ball. This allows us to work very aggressive drills even without pads while limiting the risk of injury. We also purchased the attachable QB arms.
I was skeptical of the QB arms. I have not had good experiences with this type of product in the past. However, I have been pleasantly surprised with the arms. The attachment to the pop-up is sturdy and has had no problems with sagging (which was a problem with other arm attachments I have used in the past). The durability is good and the arms held up better than expected throughout the season.
Next, season we are adding the bullet arms.
I have a bunch of pass rush drills that I can't wait to try out with the bullet arms. If they work out as well as the pop-ups they will have been a good investment.