I live way out in the boonies, and VZ is the only reasonable internet available. I'm on the very edge of service. I added this antenna to my Pepwave mbr1 alongside an omni-directional antenna. Aimed in my best approximation of the tower, these are my gains:
RSSI - 10-15dB (to 65avg)
SNR - 5-10dB
RSRP - 15-20db (from 110 before to 90)
RSRQ - ~5dB (up and down a lot)
Prefacing the speed results; Verizon service in the area is still an issue in general. I went from an average of 3Mbps (8Mbps Peak) to an average of 7Mbps (20Mbps Peak). Not exceptional, but MUCH more usable than before.