The finish quality of a schon and pechauer are reputed to be very similar. You can't compare the feel or hit of the two manufacturers directly, because they both have a broad range of cues which will hit differently simply because they're constructed differently. You just have to try them both, and decide.
Pechauer will make a full custom cue, or a customized version of a production cue. I've never seen a full custom schon, but I'm sure they'll make a custom cue for the right price, or for the right player.

Schon generally does limited production runs of cues (unique, limited, elite lines), which is a good way to get a great production cue that 5 of your friends won't have an exact copy of. But you pay for that privalege.
You could give Pechauer a call, and they'll customize the P13 for you, and it probably wouldn't cost much more than the list price. Will take longer to order though.
I personally own a custom pechauer, so you can see my bias.

I love the cue, and it has gotten alot of compliments on its looks. I've only let a couple people touch it, so I can't say that its gotten alot of compliments on how it hits.
You should just try to play with both of the cues you're looking at, or at least cues that are by the same manufacturer and made using the same materials and technique. Then you can decide what you like best. Neither choice is bad in my opinion.
cheers,
jer9ball