I bought a house a couple of years ago with a large decking area that was looking a bit tired.
I painted it with Cuprinol Decking Stain, I think I went through 4 tubs @ £30 each.
It looked good until after the winter when the stain (it was more like paint) started to flake off, and after 8 months it needed doing again.
The next time I bought Cuprinol Ducksback Shed/Fence Paint as it was a 3rd the price, still looks good for a few months and comes off every winter.
I am now in the position where I need to treat another currently unstained deck, but for the reasons highlighted above I don't want to use the same Cuprinol Decking Stain, I did think a coloured oil might be better but don't want to be in the same position after the winter.
I am open to suggestions.