By all accounts Baltic birch ply is the way forward as it’s slow grown and won’t have voids in like you’ll find in standard hardware store ply. Regular and certainly store bought marine ply will both chip and splinter badly in my experience. Birch ply from anywhere cold will be far better. I’ve not used birch ply myself as the cost was excessive compared to MDF for the jigs I needed as they’re not going to get huge amounts of abuse. However from researching at the time it was clearly easy and clean to accurately machine and you’ll find a lot of examples online of it being used for all sorts of jigs for that very reason. 
The cost seemed consistent from one supplier to another, generally expensive! 
As usual comes down to money vs quality! Avoid any grown somewhere hot though!!

Hi Jonathan,

let me know what you need and I’ll workout a price. I buy, use and sell this material all the time.
Cheers
Darren

Thanks guys. @darrenking I'll be in touch about that soon, need to chat with a couple of the other hackspace woodworkers about what we need. I'm also trying to get a bit of a guitar building group happening there.

guitar building group

@jonhodgson now isn’t that something you’d loved to have stumbled across in the past 🙂

@darrenking what's the best way to message you?

Hi @jonhodgson,

Drop me an email to darren.king@bagpress.com detailing what you are after and your delivery address and I'll see what I can do.

Cheers

Darren