I have seen a variety of options used to simplify the bleeding process. We all know our boats are a series of compromises. Anything we add to the process can also backfire on us at the worst moment.
Concern exists with the bulbs. They work great until they develop a crack. Then they can leak like an open hose. Diesel is not too bad. Gasoline is an extreme hazard. Often you find the bulb attached to a small portable tank. The tank contains the fuel and the bulb is used to pressurize the system. All well and good. If a leak occurs, it is a small leak because the main volume of fuel is contained in the tank.
Introducing the bulb in line with an 85 gallon fuel tank on one end and an engine driven fuel pump on the other is a whole different story. That minor crack and seepage leak can be come a spraying fire-hose trying to fill your bilge with diesel or worse gasoline. So if you must add a bulb to your system mandate regular inspection and no compromise replacement at the first sign of cracks or leaks in the unit.
Best option is not to introduce air into the fuel lines when changing your filter. My old fuel filter was a Ford Truck filter spin on/off.
My first filter change was a nightmare. Not only did I enjoy a Diesel Fuel bath and spillage beneath the filter, the moment I cracked the seal air infiltrated everywhere into the system. I changed my filter system to a Racor 500M
I added the vacuum gauge to help me know when the filter need to be changed.
Now when it is time for a filter change I close the fuel lines, open the top, remove the dirty filter...
replace the 2 O rings with the new ones provided.
Top off the filter with about 2/3 pint of fresh diesel. Close the filter top, and start the engine, no priming required.
Best time is under 7 minutes at sea, no spills.