I have a board with 4 sensors in a line.
I did have a few issues, but mostly ok.
Things to watch out for - sensor spacing >3.2mm to allow enough room for the o-ring.
o-ring - go for as much cross section thickness as you can. I had 0.7mm which is probably a bit on the thin side - ideally I would say 1mm cross section.
The metal caps did have a tendency to get ripped off if taking it in and out too many times.
Putting the sensors down by hand probably not a good idea as the alignment is quite critical for a good pneumatic seal. reflow is the way to go, unless your really good at hand flow stuff.
Ideally tolerance 0.05mm, but 0.1mm may be ok depending on o-ring cross section.
20-30% compression ratio on the o-ring.
