I dont't have much to share on the sys you mentioned. My gal's 1st CCC uses Letterland. Anyway she wasn't there long enough to learn much. I dont't know how true but I've heard that the tunes are different for each alphabet.
My gal was taught using MMI's method cos she attended MMI. Monte's method is to teach basic 1st sounds with the same catchy tune, like Ants on the Apple X, X, X (3 times), X is the sound of A; Balls are bouncing, X, X, X (3 times), X is the sound of B (where "X' denotes the phonetic sound). Then move on to ending sounds, diagraphs, blends, phonographs, sound boxes, 3-parts cards (pink, blue schemes), etc.
I also supplement with online resources like Starfall.