No way. SD has a lot more applications than just as Disruption bot, can be laned anywhere (he's an amazingly good solo mid as well as effective in a duo lane or a tri-lane) and can be built as a hard support or even a semi-carry thanks to good AGI growth and solid INT growth and high base damage. Hell, a solo mid Shadow Demon gets a guaranteed kill as soon as he hits level 6 (a lot like solo mid AA) unless the enemy mid hugs their tower for the rest of the laning phase, and he can be an effective ganker well before 6, too (really, as soon as he hits level 2 and gets his first level of curse.)
OD on the other hand requires a lot of farm regardless of how you play him, is fragile as hell even with a Meka, and has pretty much no real offensive capability until the midgame.
Yeah. Maximum damage they can do with level 1 ulti is 66 on the first salvo (10+56), and they lose 8 attack damage every time they attack, and it takes them 15 seconds to recover one of those bonus damage charges. They have 300 HP and 0 armor and move at a relatively slow 380 move speed, have mostly no vision radius, and are melee-range attackers. Oh, and they're each worth 100 gold so you have to be REALLY damn careful with them. Their stun is handy, but it's only a 1 second stun (up to 1.5 sec with lvl 3 ulti), so you have a maximum of 2 seconds of stun on a 30 sec cd if you time it correctly.Also the familiars are definitely fairly bad for how hard they are to use.
I wouldn't have a problem with all that if you could just bind your familiars together with Visage and just run around as a group, but you really have to have them grouped separately since they're so slow relative to most heroes (380 would let you catch a CM, but it's too slow to really run down much of anyone else) and so squishy. Hell, I've had neutral creeps kill my familiars when I was flying them over the trees in the jungle to get them into position for a gank, which is goddamned frustrating.
Shit, next time I think I'm just gonna completely skip my damn ulti... shitting out Visage's W every 4 sec in teamfights is utility enough.