Double Negative wrote in post #5448886
I've been burned by Canon's experiments in plastic before

Double Negative wrote in post #5448886
Not that the EF 50mm Mark II is *that* much different than the Mark I (really just the lens mount and distance scale) but I won't buy anything that cheap again, $75 (err, $90) or not. I do own the Mark I, but at least it still has a metal lens mount!
I dunno, I've never used a 50 f/1.8 MKI, but I did have a 35 f/2 which is built much better than the 50 f/1.8 MKII. But its interesting, the 35 f/2 is actually $250 @ B&H, I guess if they couldn't offer the 50 f/1.8 MKI at a much lower price than that, no one would buy it over the 50 f/1.4.
Double Negative wrote in post #5448886
That's not to say the optics are garbage in these low-end lenses. Usually they're actually pretty good. The rest of the lens might be questionable though. Plastic lens mounts? That's where I draw the line.
I agree, the 50 MKII was a great lens to get into low light / shallow DOF stuff, but there is nothing redeeming about how its made. 
msowsun wrote in post #5449144
When the new 50mm 1.8 mkII came out I was initially envious of the slightly faster, and slightly quieter AF. But I stayed with the metal mount version for many years. I eventually sold it and got a 50mm 1.4, but now that is gone too.
Really? You weren't thinking "what the heck is Canon doing discontinuing a decent lens for something built like a toy??" 
But really, I think if Canon could come out with something like a 28 f/1.8 built like the 50 MKII, they'd probably sell a ton of them to crop camera users. Maybe in an EF-S mount. Interesting idea anyway.