I've seen several bikes with the Prodigy. I've never owned a pair, but have had several of the LP Turbines on my bikes. RF makes a great product. The difference between the Prodigy (low end) and the upper end stuff (LP Turbines, NEXT, NS) are the Prodigy line is forged. The upper stuff is machined!
I don't know if there is a big difference between your existing cranks and the Prodigy line. Except appearance. O.K., if you get the ISIS, that's an upgrade, but, if you're not breaking spindles, it's not a necessary upgrade! If you want an upgrade, I'd say spend a bit more and get the LP Turbines.
L8R
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