PAL blues are actually my favorite SE blade, but I seem to be in a minority of one around here. Be that as it may, I can't believe the corrosion in those pictures! Were you not rinsing and patting the blades dry after each shave? That's a must with any carbon-steel blade. I've never had a PAL or any CS blade rust on me when I follow that routine.
I rinse them off, shake, and leave in the razor. It's been pretty humid here the last few days, so I think that's what happened. Next time, I may just try an alcohol bath for them.
Lots of folks here feel they get a smoother shave from a carbon steel blade versus a stainless blade. I can't tell the difference myself. They just need a little extra care to prevent rusting.
I also dunked them in 91% alcohol and still got rust. You have to take them out and dry them to avoid the rust. The upside is you can hone them on a Barbers hone and make them shave incredibly well. There is an older thread from about 6 months ago that showed how to do it. I'll be buying a hone soon and try it out.
Are the current PAL Blue Blades related at all to the vintage PAL Hollow Ground blades? They look very similar to me but I've never tried the current version.
The Hollow Ground blades are awesome and don't rust like that on me.
The ones that I have and use are "Blue Star" and I haven't had rust problems so far. I didn't have any, of any kind, when I first got my Micromatic Clog-Pruf, which was my first SE razor after over 50 years since last seeing the one I once had. None of the local stores had any, and only the HEB Supermarket even had an empty slot to eventually put a restock in. I think I've had the blades for about two months now.
Carbon Blades are supposed to be generally removed and patted dry and left somewhere over night before the next use. They will rust if left in the razor since droplets of water can hide in the razor.