Depends on your definition of 'average EV'.
The 100Ah cell size will be very limiting to range and performance unless you run a higher voltage system to compensate. I personally wouldn't touch these considering that for twice the price I could get lithium cells which will outperform these significantly in both performance and range(no peukert effect). Putting a bunch of gel cells in series is also something that will need some care because if any of the cells gets overcharged it will develop a permanent void inside the cell and you'd have to remove that battery.
If you want lead-acid, AGMs are superior to these in performance for probably roughly the same price as these gel cells.