(NO postwork. Straight Poser 7 renders)

MIKI 2 and V4 aren't even in the same league.

Miki 2 was shaped after a real woman, while V4 was shaped to match the tastes of people who think Barbie is the ideal woman.

Miki 2 has separate buttocks and a waist group, that means she can even give Apollo a run for the money in terms of bendability.
V4 is grouped like Posette. She makes good PinUps, but don't even think about doing more demanding poses with her, as her thighs start to bulge and deform almost instantly.

Is she perfect ? Not even close,
While V4 has way too high underarm-cuts (Easy to fix in P7 but impossible if you use D|S), MIKI 2's shoulders and ellbows can need some help, too. (Again, easy fix in P7)
Also her inner mouth mesh is way too dense, resulting in unnecessary waste of your systems RAM.
(But at least she doesn't share MIKI 1's 10.000 polygon eyes)

She lacks the variety you can get with V4's add-on morphs, but if you take the time to learn using the P7 morphbrush, there is no need to wait for any costly DAZ add-on morph packs:
http://market.renderosity.com/mod/forumpro/showthread.php?thread_id=2693349

Just do them yourself. It's fun, and it will make you a lot more proud if you can say "I MADE it myself", instead of "I BOUGHT it myself".

And of course MIKI 2 has face room support which V4 hasn't.
Not to mention that she has the very best expression morphs of any Poser mesh around.

So if you want to have a realistic looking mesh which can bend like a real woman, there is no way around MIKI 2.