the LED lights are worth the high dollar cost, and cheaper over time (more cost effective but higher initial cost) especially in a less than perfect floor operations.
I am of the opinion that if Mitsu-UK had never had a light bulb life expectancy concern/complaint, they never would have come up with the optional $ LED lights.

Must admit have used the ones from our Belgium friends, but the oem ones originally fitted must be **** quality as well. They dont even last a full shift

How rough are the floors/ground where these trucks are? the bulbs blowing or is it just the filament breaking from excessive vibration and jarring? Have this problem with on customer on my route, filaments are breaking from the jarring from the VERY rough floors

Edited: Didnt see post about ground surfaces

what make bulbs are you using?
We used to have loads of problems with cheap bulbs blowing, especially TVH bulbs they are crap.
We fit only Osram bulbs and they last well. Its not worth fitting cheap ones as you loose any price benefit going back and forth to the truck!!!