kinda playing off the last post... methods need to be catered to the type of light, if penetration is the question with LED's then something like a SCROG setup would seem ideal for LED's... without adapting your methods to maximize yield for the limits LED's have, it handicaps the technology... the same was done for HID's by implementing current indoor techniques, this LED technology is just another evolution, IMO... is it the best currently available, that's the question at hand.
this is the demo that specifically drew my attention to growing a plant in the same straight forward(no training) method one is accustomed to indoors:
http://www.youtube.com/watch?v=_CtROw3uiVg
(you can find other related LED vs. HPS flowering comparisons)
now there's no debating the stretching and lower yield on the LED side, however, factoring in the operating costs LED's are actually the winner. Now as growers and consumers, we generally want the most bang for the buck which is only natural. Its just my opinion, but I think if this same side by side demo had been done using SCROG on both sides, that the HID would still out produce the LED in terms of total yield, but we would see quite an increase on the LED side in terms of power cost/yield ratio. A couple other bonuses I see for LED's in this, especially if multiple panels are used, no serious heat signature, possibly avoiding IR detection and lower utility bills, that might draw suspicion(depending on your total use) I know years ago these were both serious concerns for myself indoors.
Finding the right balance of red/blue, I would think each strain would have an ideal balance, so a panel with the ability to shift(add/subtract) rows/rings of red or blue would be more of a multi-purpose light... so this is still something that I consider "in progress" research left up to the grower.
The few demos I've seen make me believe LED's are more than ready for cuttings, veg and mothers. Already mentioned, negatives for LED's the initial cost, yields seem lower; positives, overhead of power consumption, extra cooling equipment unnecessary, minimal light intensity fade(vs. HID bulb replacement after 6-9 months). I'm sure someone could do a real thorough cost analysis and find a definite case for LED's, like most "energy efficient" alternatives there is long game on the savings and return... one would think this would cater to the marijuana grower mindset, patience.
Addressing the initial cost for LED's, you could fabricate a similar model using the high quality CREE LED's for much less than a commercial model... with a forum like this, buying hardware in bulk, sharing the cost and kicking around homemade schematics seem like the perfect marriage for a solution.
but I agree with Hick, more unbiased, tangible comparisons need to be offered, especially if they expect people to pony up $1400.