I tried the recipe below tonight using all Splenda, but they came out more fluffy & cakelike, almost like scones texture, not the usual chewy texture at all and they weren't overdone, so my guess is that's the lack of brown sugar & lack of carmelizing nature of Splenda...? They do taste slightly of fake sweetness, probably because that's a lot of Splenda using 2 whole cups to replace all the sugar. If you could use the half-sugar, half-Splenda, like they're now selling as "baking mixes" that would probably taste better and work better, but that won't work for a completely sugarless diet. Calorie-wise, I don't think it's enough calorie-savings vs. the taste & texture, since you still have all the fat with the butter or margarine anyway, let alone Splenda is plenty expensive, so for me I'd make them with normal sugar, but they still hold together & taste okay if you wanted to try making them for a diabetic or someone who cannot have refined sugar.
Oatmeal Raisin Cookies
2 cups flour (whole wheat if you want it to be good for you)
1 tsp baking soda
1/2 tsp. salt
1/2 tsp baking powder
1 cup butter (or margarine)
2 cups Splenda (or 1 cup white sugar & 1 cup packed brown sugar)
1 tsp vanilla
2 cups rolled oats (old fashioned)
1 cup raisins
Bake on a greased or non-stick cookie sheet, at 350 degrees for about 15 minutes. Yields approx 4 dozen cookies. Non-Splenda version = 2 Weight Watcher points per cookie.