Two things. That is an old article from Solar planet. The SR series was superceded by the SP series years ago (five years at least).I was looking at the SR+:
"The new Solbian SR+ panel by Merlin Solar is the first marine solar panel to use Panasonic’s Heterojunction with Intrinsic Thin-layer (HIT) cells, now the most efficient solar cells on the market. "
And the ruggedising of the SR so they could be walked on meant that the efficiency of the cells were further compromised.
You will likely not walk on the roof tent shell, so there's no reason to compromise and get some that is compromised because they're designed to be walked on.
SR Series - Solbian
The monocrystalline high efficiency SR cells are sandwiched by two patented metallic grids. The metallic grid on the front of the cell is specifically designed to maximize the current harvesting. On the rear of the cell a second grid provides extreme resistance to cracks and over-bending. The...
www.solbian.eu
SP series - Solbian
Flexible solar panels of SP series are at the top of the range, thanks to the use of selected SunPowerTM monocrystalline silicon cells
www.solbian.eu