This is a great question to weed out possible problems traders. Of course, since I dub with very nice equipment I look for the same. The key here is to trade with people with similiar equipment as yours. In addition, always be honest with your set-up. Often, good traders will dub for blanks if they are not comfortable with what they might get in return.
Communication is so very important.
Not only will they appreciate it, but they might want to change the trade. Keep a log of your trades. I have a form developed, so once I agree to a trade, I can record the traders name, email, home address, phone, cases or not, tape type to dub with, approx finish date, and of course what shows I am sending and receiving. I also have a box to check when the tapes are sent and then again received. This also serves good purpose for continued trading with the same person, as you can always go back through your successful trades and email the person for additional possible trades.