@kagurasnowsurfer I've used PowerRides.  They are definitely helpful to stiffen up the interface.  They're not as stiff as my custom stiffeners though, even when I stacked two pairs together.  That's why I sold them.

I found another company that makes boot stiffeners and I'm trying to get those in the store for next season.

So I bought a pair.  They definitely stiffen up worn out boots but my rear foot is getting crushed by the front of the stiffener.  I currently have 10mm pad to  lift the heel.  I might increase the pad thickness to see if it helps.  

any tricks or suggestions?

@angry4nus When I package the Trenched Boot Stiffeners I include some pieces of EVA foam.  I couldn't find high quality stuff with the sticky back so I apply two sided tape to the foam before shipping.

So...  if it's digging into your toes you would apply the foam higher up the stiffener, maybe ending 1cm from the toe edge.  This will put more pressure up higher over the top of your foot and relieve the pressure on your toes.

Also, you will need a strap.  Without a strap near the top of your boot, the forward flexion will push that plastic stiffener right into your toes.  With the strap, there's less of that forward flexion and the stiffener remains in the same position relative to your foot, no toe pain.