Stumbled on a sack full of M737 first gen spd pedals, so ended up putting them on most of my bikes over the summer. They are heavier than quills, but I thought I would try them, as I really like to ride in my spd sandals. Most of my lighter bikes already have newer spds. Come winter, I put platforms with toe clips back on my rough weather bike, and have to admit that I really feel the difference on the hills, particularly short sharp rises, but overall on the long uphill slogs. thinking about getting some winter shoes with clips now, if I find any on sale.
I still might be using platforms for some tours, but since most of my trips are about saddle time and distance, will probably stick with clipless. My last tour averaged 120 miles a day, and I don't think that I could have done that as easily without them. The vintage retro curmudgeon in me is sad, but at least I am using vintage spds!