Trouble deciding between ThinkPad T450s and Latitude E7450

I've been reading NBR, searching Google, and browsing all of the retailer stores and outlets for the past few days and have narrowed my 14" business class ultra book search down to the final two, but can't decide which I should purchase. Hoping for some help from the NBR crew who may be familiar with both notebooks.

I'll list my important, must-have's first:
- Light! - Wanting to be under 4lbs, closer to 3.5 lbs would be preferred
- A good, future proof, CPU that can handle a nicely...

Trouble deciding between ThinkPad T450s and Latitude E7450