I've got a nice set of Parkers, but I doubt you really want to spend that kind of money, unless you do a lot of tubing. It would take about 5 bills to have a new kit on your doorstep....
I have the one pictured it works fine any time I used it.
Can you move the rollers out and install a metal backer
More lubricant and less pressure. It should take a couple of passes with adjustments to make a good bead.
Here is a decent video on the process using a Parker tool: