Mastercoin,
- uses irresponsible implementations of Class B transactions.
- creates outputs that aren't spendable by any wallet.
- greatly privileges Windows users.
- and doesn't have a specification that describes current implementations.
I feel strongly enough about these items that I'd rather see some sort of resolution than sleep like a normal person. I don't feel like it's my place to offer unsolicited solutions to the problems I'm posing, however would be happy to discuss my ideas on the subjects.
And if consensus is that the items I bring up are not problems, take this as feedback from a "long time mastercoin user" that the project feels out of touch, lacks on the PR front, and has direction at the expense of overall quality.
I'll let one of the devs weigh in on the class B stuff. We do plan to have better options for non-windows users soon. Omniwallet should be a good solution, and for those who want to run a full node, we want to have a full desktop client too (possibly a port of Masterchest using mono). We hope to greatly improve usability on all wallets which we sponsor.
I think the spec is accurate right now, but if you've found something that is out of date, we welcome pull requests

Thanks for weighing in.