Well, here is my report. Mind you, very preliminary.
I sprayed some Stynlrez. It seemed to spray ok but that has not been the issue. Cleaning the brush went better though. I did have to insert the needle a few times and wipe. So, there was some paint in the body closer to the needle bearing even after spraying lacquer thinner first. Paint seems to collect there. I waited for the brush to sit for a few hours and tested the needle movement. The good news is that the needle was not locked up with paint as before.
I suspect this brush behaves differently than what I am used to. The needle tension remains rather loose compared to what I am used to. The other extreme of this is my 200. That needle is tight, very much so. In terms of tension, my 155 is in the middle of the 2. It is looser than the 200, tighter than the 105. I suspect I will need to flush the 105 a little different. It seems a little more difficult to clean than the other two. Again, only one test into it, so very preliminary. But, I tried a challenging paint so... probably good to go.
That is about all I can report at this time.