Astra SP is my workhorse. Sharp, smooth, and cheap. Works well in every DE I have, and I have quite a few. From Lady Gillette to R41, and everything in between, the Astras just work.
Nice Bokhara. Russians have never let me down with Polsilver/ Super Iridiums my favorites with the exception of the brown and gold Wizamets. I have a small stash and when I hit 3 months and enough posts out they go.
I had trouble deciding between Ladas and Voskhod but I ultimately went with the latter. It's a smooth, comfortable, no-nonsense blade for me. I'm still eyeing those Ladas blades but I have to remember something about a "budget."
Red Personna's for me in my Merkur 23C razor. No razor burn, no irritation, very few weepers. Contrast with the Feather blades, which I had weepers most every shave, even being as gentle as possible.
Gillette 7 o'clock yellow. Even when I first started going through my blade sampler, they really stuck out. Now I have a hard time trying new blades, and usually wish I hadn't. However,I'm less particular in certain razors. Pretty much all of them work well in my Superspeed, and adjustable.
I've used IP and Derby for years. Recently, I found Derby works best with my Parker Variant, providing excellent, irritation free shaves. I'll stick to Derby now.
Astra SP's have been my go to blade for the past 3 years, they seem to give me the best overall shave. I had good luck with Bic Chrome Platinum also. They aren't as sharp, but seem to do better on my sensitive areas on my neck. I get less irritation from them.
Easily, Astra SPs. Sharp, effective, smooth, and give me the best, consistent overall shaves from any blade I've tried yet. Plus, I can pick up a carton of a 100ct. for around $10. Can't beat that.
As a recent recruit to the Cartel, I would recommend either Voskhod, Gillette 7 o'clock Green, or Gillette Silver Blue. Long live the Rodina!