How long have you worn the 14's around the house? Wear them for 30min to an hour and see if they give a little bit. Try wearing thicker socks with the 15's
that's all I can recommend fam.
The verdict is in...I'm going with my true size 14.
When I first put them on I was wearing thin socks and it felt like they were strangling my forefoot. Four hours later the difference is dramatic.
The 15's obviously felt more comfortable when I first put them on...until I started walking. When my foot made the natural bend at the ball, the shoe would fold in and pinch my foot. There truly is more length on the XI because I had damn near a full INCH of toe room. The only reason the 15 didn't flop around is because I tied them tight and have a decently high instep. As soon as I loosened the laces just a tiny bit, I could shake the shoe around while it was still on my foot.
When I put the 14 back on, I had the normal 1/2 inch of toe room and the shoe bent correctly with my foot as I walked. As time went on the shoe already started to mold to my foot, so I tried some thick NBA and Elite socks and I didn't feel as much pressure in the forefoot as I did initially. It feels like a glove on my foot now. Loosened up the laces a bit and I can double-sock no problem.
The ONLY problem I have with this shoe is the height of the toebox. It's really lower than the past Lebron models. But it has the length, and with time I'm sure the insole will flatten a little bit opening up more room in the toebox.
Lebrons are finally back to TTS.