I am in the "don't get it camp", my Roadster was fine without power steering, can't say I noticed the difference between it and my 4/4. Also these cars are kept for many years and it is just more bits to go wrong.
I say spend the extra money on gym membership
It could help owners with arthritic hands keep their Mog longer.
(I'm OK at the moment but may need it within the next 5 years, but would have it adjusted so that there was no assist above 15mph)