Living in PHX in the summer means very, very, very hot ground. Unfortunately running barefoot is not always an option, or even in my time-honored Vibram Five Finger KSOs. Occasionally people will email me and say "go running early when it is dark." I am out the door at 4:30am most mornings to beat the heat, but trail running is not an option in the dark for me due to the vast nocturnal wildlife and insect world that takes over the desert. One must see where they are running in Phoenix if it is dark! So, on go the F-lites. 
I've tested them with the insoles and without and as you can see, being the minimalist I am, I ripped the insoles out. They serve no purpose and feel offensive to a foot that has reconditioned itself to run naturally. Once they came out I felt that same great flow and movement I feel in the Vibram Five Finger or barefoot.
This is an outstanding shoe for those races and times you must strap on a shoe. Very light, very funtional and actually kinda fun to run in (and I don't say that about shoes). As always, I think insoles are gimmick for the over shod world, but thought I would include a couple of shots so you could see for yourself. Seriously, they are minimalist insoles compared to the over cushioned running shoe world, but once they came out I felt the performance of the shoe enhanced due to less restriction and padding. Its almost like being in a smoke-filled room and then you step outside and take in all the fresh air. That's how I felt when I removed these damn things. Dramatic? Perhaps, but that must mean I've fully converted...
FROM INOV8:
The Inov 8 Men's F-Lite 230 Trail Running Shoe features a thin, low-profile sole for race day and Facia-bands to aid propulsion on training runs. This versatile shoe allows you to train efficiently and kick serious butt at the races without the need for a quiver of footwear. Inov 8 used a nylon mesh upper to make the F-Lite 230 as breathable as possible, so your foot stays nice and cool from start to finish. This shoe also uses Inov 8's sticky rubber outsole for excellent grip on roads and tracks.
Bottom Line: From training to race day—one shoe for everything.
