I like the powder route because it is hard to swallow enough caps to equal a heaping Tablespoon (or more) of green food powders.
In my raw world green powders like Vitamineral Green, spirulina, chlorella, wheat grass, and kelp are real food. I use a heaping Tablespoon of VG and a teaspoon of all the rest to enhance, mineralize and supplement all my green smoothies. Maybe it is an acquired taste, or maybe it is finding the right green powders. Since going "supergreen" I find simple smoothies of fruit/greens don't taste green enough and don't satisfy me.
Prior to finding Vitamineral Green I tried some funky tasting green grass powders, especially those flavored with chocolate and/or berries. Yuck! I'll take my green powders without extra flavorings.

Seriously, I say Vitamineral Green is the best tasting. Spirulina comes in second.
VG (or any similiar Jameth Sheridan formula) claims to provide 150%RDA of iron, 33%RDA calcium and 4.4 Grams of protein per heaping Tablespoon, in addition to many other nutrients, probiotics, etc.
I supplement with 300mg calcium citrate/150mg magnesium oxide, and Host Defense mushrooms which both come in caps that I empty into my green smoothies, also 5 drops (2,000mg) of liquid Vit D3 from cholecalciferol (combed from sheeps wool), Jarrow's Methyl B-12, 800mcg folic acid, and finally 2.25g Vit C (ascorbic acid). All these supplements are part of the 2 month program "prescribed" by a Registered Herbalist/Aromatherapist that I sought help from. I will probably continue to take these supplements even after I'm done with the herbal/essential oil part of the program.