The only way to find out is to try. If you ask half a dozen people you will get half a dozen opinions.
Things that work well for one marketer may not work for others, and just because someone tells you that a particular method doesn't work, doesn't make that true.
If you look round the internet you will find people making a success of almost every technique imaginable. The important thing is to choose one method then track and test it, tweak it track it test it and on and on until you get the results you want.
Personally I've run successful ads and unsuccessful ones. I can't even give you any reasons for the success or failure. All I can tell you is that what you think is a good ad and what people respond to can be very different. The only thing is to test test and test again. I remember one headline on a squeeze page where changing "Learn the secrets of..." to "Discover the secrets of.." tripled the opt in rate. One word! Why? I have theories, but they could be as easily wrong as right.
Nobody can give you advice that is foolproof. Go to your library and look at magazines. Look for direct response ads that have been running for years and make a swipe of the headlines because they will have been tested to death!
Always be aware of your target market. For example years ago direct marketers discovered that in the USA addressing the envelope in red ink increased response, trying the same technique in the UK killed the campaign.
Even the fonts you use will make a measurable difference, as can the color of the font, the background, the graphics etc, etc.
I'm going to say it again because it's so important. Track it test it tweak it and do it all again until nothing beats your control.
