Theoretical speed ≠ real-world speed. LTE should trump HSPA+ all day long, in both directions, but the reality is that in many areas HSPA+ matches or even exceeds the speeds of LTE due to allotted bandwidth, network strain, etc.
It's a matter of service quality in your local area. In my neck of the woods, download speeds are slightly higher on Tmo's HSPA+ than VZ's LTE, with VZ taking a notable edge in upload speed - though both services are plenty fast enough both ways for ordinary usage. Tmo's HSPA+ continuity of connection is far better here, though, and ping times far lower (makes a big difference when you tether for online gaming).