I'd say if you can get a rear Surly hub for 50€ you should get that as it'll be higher quality and that's an unbelievably low price!
Also, if you speak in € then that means you're probably not in the UK and would required shipping + customs tax + VAT (thanks to the majority of the UK voting for Brexit) so not worth buy from anyone in the UK unfortunately.
I'd say if you can get a rear Surly hub for 50€ you should get that as it'll be higher quality and that's an unbelievably low price!
Also, if you speak in € then that means you're probably not in the UK and would required shipping + customs tax + VAT (thanks to the majority of the UK voting for Brexit) so not worth buy from anyone in the UK unfortunately.