Being 6'4", I have size 13 feet but for my boots I'm size 14. My boots happen to also be Ride boots (Anthem Boa) so I know exactly what you mean.
I ride a pair of Union DLXs in L/XL. They fit nicely with plenty of room for width but not too much. For even and centered toe and heel overhang I only had to adjust the toe ramp all the way forward, without adjusting the heel loop, so they fit well.
The ankle strap is only on the 3rd out of 5 length settings and the toe strap on the second-to-last setting, so I think it would be safe to say that there's even be room for size 15 Ride boots, even though Union says that they go up to size 14.
My one complaint is the toe strap because although it does cap ride's boots (flat toe box shape), it's a little awkward to get into position. That's fine though- you can buy Union replacement parts from the C3-store website which has a kit for Union's higher-end toe strap which is much bigger and more cup-shaped if it's a problem.
You also get a lifetime warranty on the heel loop and base plate, so I think it would be a pretty good binding. I'll post pictures some time.
Hope that helps.
2012/2013 Season-Critical Statistics:
Days Riding: 9
Parking Lot Misbehaviors: 2
New Tricks: [B]5/B]
Deepest Powder: 1.6ft
Skiers Sprayed: 31,786
Last edited by Gdog42; 11-12-2012 at 07:11 PM.
Reason: To get rid of random links in text