I also own a little bramper and while it's a little cumbersome to use, I find it to be very powerful. Looking at the current bulb ramping docs I find the functionality still a little wanting. It seems like the only way to specify the ramping is by picking a positive change (which would preclude going from night to day) in stops at an arbitrary point in the future, meaning you'd need to know ahead of time how the light would be changing. With the bramper I'm able to watch the histogram on the camera and "chase" the curve by altering the rate the exposure is changing. I can see the power of being able to do keyframes if you can recreate a scene that you've done before but for dynamically changing conditions it's almost useless.
Thank you very much for implementing the Guided Bulb ramp
I got my usb cable today and I just tested it... it works great,
I posted a video of my test, video guided bulb ramp
PS:AV lock is really important to avoid flicker
new video showing guided bulb ramp, no post processing