I'm not interested in this service, since my account isn't enrolled in a signature campaign, so i don't get payed for posting anyways.

That being said, i think it's a grey area...
For both the OP as his clients, this might be a win-win financially... The OP gains more per post as when he would join a sig campaign under his own name, a higher ranked client can make more posts for his sig campaign than he could possibly make by himself.

I'm not sure if this system would be considered cheating by sig campaign managers tough... They pay a (high ranking) member for the space under their sig, and that's what they get... I don't know if there is anything that can be said about "who" wrote the post... The account owner, or a thirth party.

As for the forum quality, a lot depends on the OP... If he has loads of in-depth knowledge about many aspects of the btc ecosystem (technical, altcoins, trading,...) AND he picks a new list of threads for every new client, and he makes sure all posts are unique, on-topic,... I don't know if he would deteriorate the forum quality per sé...

@OP: instead of giving away vouches in private, why don't you make 5 posts for anyone in this thread and post the publicly? That way, anybody can look at your writing style and knowledge.

As a conclusion: i would not want to use this service myself, nor am i certain if this service would be "cheating" sig campaigns, or be considered spamming by DT members... I think the service might be "grey area". That being said, i do wish you the best of luck!