This is a great discussion. I have been trading for over 6 years part-time. I never had any REAL positive results until starting to trade with order flow, after being introduced by a friend to the basic yet effective Time & Sales information. However I really only ever made me any real decent consistent Money after learning and following some of Kam Dhadwar's (L2ST L2ST - Trading Futures Online- Learn to trade futures online) MarketDelta Footprint execution setup's over the last year or so. I am still trying to perfect the techniques and Order Flow based setup's that they teach at L2ST, however they are honest enough to say that each setup takes take time to master. Which I respect, as I have experienced that my timing improves each and every day.
However the very interesting thing to me is that ONE of the exact same set-ups that I have learned from L2ST's Kam about 10 months ago, is what Order Flow Analytics is selling as a product. I personally do not feel that you need OFA, you can just use Market Delta, He explained this set-up on the footprints using the VPS (Volume Price Statistics) Indicator for tracking when the high volume buying gets trapped at the high and high volume selling at the lows, then look for them to Bail with their poor trade location out of fear, and profiting from these traders stops getting triggered. I learnt that he uses the FootPrint Price Statistics Indicator using pullback data only in MD to track what OFA call Commitment Of Traders (COT). The Risk\trade management was also explained, by using the overall Delta of the bar itself. HOWEVER the great thing is with MarketDelta you can apply this concept to any market and any time frame! i have seen it and traded the same setup on many markets, including Mini-Dow, Nasdaq and even Crude Oil and other commodities. You see it everywhere. But this was just one of the Footprint\Order Flow setup's that I learned, there are many more that L2ST still teach, some of which use a combination of the Order Book (DOM) and the resting orders, The MarketDelta Resting Bid\Ask Tool, Time & Sales alongside the MD Footprints. However you only really need 1 or 2 to be consistently profitable. So what i am trying to say is that IMO MarketDelta can do exactly what OFA can do but with more FLEXIBILITY :-) which is always good.
Like BGTrader said in earlier posts its worthwhile checking out kam's videos at L2ST - Trading Futures Online - Contact Us, as he quite nicely explains how to use market profile and auction theory concepts for price based set-ups and levels to trade, however using Order Flow for execution, timing and trade management.