My personal comparison of TSER (Total Solar Energy Rejected) data among brands. Do take it with a grain of salt.

Tint series that belong to same tier will provide comparable (but not exact) heat rejection performance.

Tint series that belong to higher tier generally costs more.

Tier 1:
V-Kool VK and X series
Huper Optik (All)
SolarGard LX series
3M CR series

Tier 2:
V-Kool K series
Nano-Tech (All)
SolarGard HP and Sterling series
3M BC and CS series

Tier 3:
V-Kool OEM series
SolarGard Non-HP series
3M FX series

Consider also the warranty length. 5-7 years warranty are pretty common now.