According to Direct Mail News, in 2012 the average response rate for direct mail was 4.4%. As for your conversion rate, I think it will depend on your business model. For instance, my company's model is business-to-business (b2b
) and most of our deals take up to a year to work out and they typically are 6 figure deals. So, for us we did not technically get a conversion until perhaps 6 months of doing direct mail campaigns.
We did not use another company. We created the letters, purchased the envelopes, and printed the content ourselves.
I've never heard of Troi mail. Don't think I can be of much help there.
However, my advice is this: give it a try. You may have to stick with it for a few months though to actually see results. If you have budget constraints you may want to consider other options if you aren't willing to make a commitment to this.