At the risk of incurring the wrath of Moraghan - I used the RW FIRST schedule for my first ever marathon in October 2010...
At the time my 10k pace was 7:15 and - looking back at my Garmin Connect stats my first 10*400 splits were @ 6:08 - 6:03 - 6:09 - 6:05 - 6:04 - 6:03 - 6:08 - 6:00 - 6:00 - 5:49 so 70+ secs below 10k pace... And yes - it nearly killed me 
Would I use it again? Probably not... To be honest, it took all the pleasure out of running for me as I felt I was battering myself in every session. HOWEVER - I started with a sub-4 marathon goal and ended up finishing fairly comfortably in 3:34
As it was my first training plan, and the first time I had really done speedwork it taught me A LOT about pacing, perceived exertion levels, speedwork, different sessions etc... all which I have taken away with me
Since then I have been on a higher mileage diet, focussing on base-builidng and longer, slower stuff with regular tempo / interval / hill sessions thrown in and I have to say that I'm actually enjoying running again now, instead of dreading that next 20-mile long run at MP+20s!!!
Posted: 20/01/2011 at 10:43