Changed out a room at work last month with something like these...
Metalux 8 ft. Linear White Integrated LED Warehouse Strip Light with 8176 Lumens, 4000K, UNV Voltage-8SL8040 - The Home Depot
Had 4 fixtures. Each had 2 8ft T8s. Smaller, lighter fixture. No bulb. Just a strip of about 500 LEDs. So when it dies, you change the whole fixture. Originally they got some smaller fixtures with 2 strips abought 2ft long and 1.5ft apart. Too dense of a light. Blinding and made a lot of shadows. These spread out the light better and hung directly on the old fixtures positions. The ones we got are brighter and much whiter. They are dimmable, but we don't have that option in use.
Mitch, did you only use half as many bulbs? With the whiter light, it appears that is what the recommendation is.