I'd stick with the DeeZee since it is a bolt on and this requires drilling holes. If the tailgate lifting is a problem then this might be better solution. Sounds like that this would be a replacement for DeeZee with added bonus to help raise the tailgate.
I have the Dee Zee and love it. I looked into the hoppy but the info I found said it wasn't compatible with our 4th generation Rams because there is already a tailgate assist built in.
Well I have both installed. works great, the only thing is that when it goes down it comes backup a coupl of inches, I think as it is used this will not be the case, even so not a big deal.