An ounce and an eighth or ounce and a quarter steel #2 at ~1400-1450 fps will do for pheasants on the 90%+ of chances one will see on pheasants as they will be under 40 yards and more likely less. If your opportunities are mostly greater than that, look at your hunting practices and change them as you are doing something drastically wrong. At $10/box ($9 on sale) it sure beats out anything else for cost effectiveness. The flat I bought cost less than the 2 pounds of TSS you mentioned and will last me 3-4 years on average depending open how often I hunt non-toxic lands.
In the 28 ga I would go with bismuth as it is cheaper. Or, carry a light 12 ga and shoot steel 6s or maybe 5s. I've done that for 20 some years without problems. I can get these shells for $7/box regular price.
Or, use a 22 LR, 22 WMR, or 17 HMR if legal. >50 yards is the beginning of rifle territory.
