Burkert 6011 is ok and good for our application, and there are more different solenoids you can choose from.
Don't want to limit your choice to burkert 6011 only.
There are more, virtually all the major industrial solenoid valve producers have the solenoid valves that fall in the same category as burkert 6011.
As I mentioned in another thread, SMC, Parker/Honeywell/Paul, Mac, Numatics/ASCO, clippard, humprey/konagei, and more brands, do have solenoid valves that are in the same category as burkert 6011.
And there are low flow, low power consumption type miniature solenoids exist as well, clippard mouse solenoid is one of them.
Bettatail, you are correct that there are many solenoids out there suitable for continuous duty cycle. The problem is that 99% of the hobbyists on this forum have no idea what to look for or even where to locate one. The Burkert is popular because it's proven and we know where to get one. I also believe 10-32 ports scare many of use too. That cuts down a huge number of what's available.
Perhaps you could list the makes and models 2 way, normally closed solenoids rated for a continuous duty cycle you to work well for use. Also, knowing the port size and voltage would help.