I've been pretty much training exclusively on my platforms. I have hotspot issues with pretty much any shoe that's not a specialized bg wide, with just the right amount of arch support and wedges. While I have a pair of SPD SL's, I find platforms to be very convenient. Just make sure you have a toe clip or something to hold your foot in the same position.

Also, I've been looking at some stainless steel insoles to put into my tennis shoes that'll improve the stiffness. I'll probably have to rig something up with that insole to have some sort of arch support though..