I know proxies are fine by and large only not at tournaments. Papercraft is downright frowned upon by most store owners as it's indicative of lost revenue. I can't speak for Eric at Wonko's but he loves the hobby and imagine he'd frown at the idea of it.

To put it in perspective imagine showing up to a magic event with cards you had printed online.

I for one understand the idea of trying before you buy. And paper craft is one sure way to do it. I mean dropping mint on models you may not use should be avoided. But just not in paired events.