Best device to go with stretchy ball sacs

[solarpower]

As a man who has been into ball stretching for a long time I am finding it almost impossible to find a chastity device that I cannot pull my dick out of. My balls can stretch forward 4 inches, and with the CB6000 for example I can slide the device enough forward, when soft, to allow me to pull my dick out, leaving the device only held on by my balls. Anyone got recommendations for a long term chastity device that my partner can lock me in that won't have this problem?
Also often have a problem when I get hard in most devices that the device is simply pushed forward by my cock, pulling my balls further from my base, causing pain and allowing a full erection.
Note: I am uncut, 6 inches, decently thick

[locknload]

Only way to stop that is to get a PA.

[solarpower]

While a PA is an option, I am hoping to find a device that does not require it at this time. But I do appreciate the input.
I specifically am wondering about the Bird Cage, Boy Trainer, and Stainless Steel Chastity Cock Cage (http://www.mr-s-leather.com/CB310/stain ... -cage.html) as these are the three that interest me the most.

[kayfox]

I have the exact same problem! Can pull my shaft free of any device I've tried, and I'm not willing to get a PA... Plus a PA wouldn't solve the biggest issue I have.

I currently have a CB6000S which gets pushed up when I have erections and causes painful tugging on my balls. I've tried the CB3000 and birdlocked, normal and mini versions. All have the same issue that rather than preventing erections, the erections push the devices up and cause pain to the point where I give up and remove them.

If anyone has a solution, I'd love to hear it.