Wednesday 29th August 2018: 6.45pm. Location: 53.3795280456543,-6.597754001617432.
Tesco Mobile Ireland just flipped on 4G for me free of charge, which was nice of them. Speed difference:
3G: 6.4 mbit down, 2.8 mbit up, 24 ms ping
4G: 28.7 Mbit down, 21 Mbit up, 30 ms ping
So, about fourfold faster down and eight fold faster up. Nice!