Pros: Sharp, smooth, and forgiving. Consistent performance. Very inexpensive when bought in bulk.
Cons: Occasional rough blade slips through QC.
The most important component for a double edge (DE) razor user is the blade. True, the razor is pretty important, but it is a lot easier to find a razor that one likes than blades. Interestingly, with Gillette and Schick flooding the market with various multi-blade cartridges, one would not think that there would be all that many choices in DE razor blades for a market segment that hardly makes a blip on the radar, yet there is actually a dizzying amount of blades available, and it can be an arduous process to find the one that works best for your face.
What complicates matters is the fact that many who use DE razors will own several different razors (or, in my case, about 150), and some blades shave differently in one razor than another. So, say you had a rotation of 10 razors, and purchased a sampler of 10 different blades which would create 100 different combinations. To get a good feel for any razor/blade combination, it should be used for at least a week, so it would take almost two years to go through all of this. The simple solution, of course, is to find the one combination that works best and stick with it, but, if you collect razors like I do and want to use them all, you'll need to find a plan "B".
My plan "B" became the Astra Superior blades that are manufactured in Gillette's factory in St. Petersburg, Russia, from which several other brands also originate. Of the 10-12 brands of blades I tried, the Astra proved to be the most consistent performer regardless of what razor it was in. The stainless steel platinum coated Astra Superior is a very sharp, smooth, and forgiving blade that always provides me a close and comfortable shave. Why do the Astra blades work so well in different razors? I'm really not sure, but I have read those exact sentiments from others, so it's not just in my head.
Not only is the Astra a very high quality blade, but they are also one of the less expensive brands available, especially when bought in bulk. I found one retailer selling these blades for $100 for 1100 blades, and, at that price, I can afford to use a fresh blade every day if I want and still be way ahead of multi-blade cartridge prices.
The only negative issue I have with the Astra Superior is that I occasionally come across a bad "scratchy" blade that pulls my whiskers and irritates my skin a bit, but I don't get too worked up over this since a bad Astra is still a lot better than the best offerings from many other blade manufacturers.
Interestingly, I did not care for these blades the first time I tried them and stuck the remainder of the pack way back in my closet to be forgotten for many months. But, after going through several other brands, I pulled these back out to give them another whirl and fell absolutely in love with them (to the tune of stockpiling over 2000 blades). As I said, it's tricky finding the right blade, and it really pays off to revisit the ones that didn‘t impress immediately because you may discover your "one and only" like I did.