Pedal-Pi vs PedalSHIELDs

I'm thinking of building a pedal for my brother (I don't play guitar myself), and would like to know opinions about / the differences between the Pedal-Pi and PedalSHIELD(s):
- Does one have better sound quality?
- Is there a (big) difference in costs?
- Does one have more options while playing?
- Does one have more readily available effects?
- Any other pros and cons?

Thanks for your replies!

Awesome! Thanks!
Came across a few errors in the text:
In the Pedal-Pi section, it says: "Building the board is more complex than the UNO but simpler than the UNO"
In the summary, 3rd paragraph: "This boars has a lot of fields..."
And the last paragraph: "Believe me, the UNO sound quality is not miles away from the other too,"