When I was working in the training and education dept for CEDIA, I ordered in the Panduit and the ACOM units to add to our show-and-tell handouts that we passed around during the Residential Install BootCamp classes.

Dave Pedigo and I also used them during a rack upgrade in the BootCamp lab spaces in the (now former) CEDIA HQ in Indy.

I liked the ACOM slightly better in use, but both are great.

One note in favor of the Panduit: Their unit had a little more flexibility in the groove spacing. It could bend to open a touch wider if you were combing some bundle cable or 14/4 or something larger diameter. The ACOM is pretty rigid, and it's really for Cat and RG6, and maybe 16/2 or whatever as long as the diameter is close to the same as Category and RG6. :)

I used both of them on the project, and they are cheap enough that I would purchase both to have in my bag if I were actively out cabling up projects today.

If you only have the budget for one, you really can't go wrong either way.