Each one has its pros and cons. But I prefer one way links. Good luck.
All three link building are good until and unless you don't abuse it. Although, I have set the priority of link-building techniques:
1. One Way Link Building
2. Three way Link Building
3. Two Way Link Building
P.S: Don't compromise with your SEO linkbuilding techniques.
As per me only One way link building effective rather then two way or three way. According to me two or three way is harms to your website and you may penalize for it while from one way link building you can create reputation of your website in search engine.
I think they both have strong value. But I'm sure most will agree that three way is the best. Their is nothing wrong with two way (reciprocal) like most people think, the trick is to make sure that you do not have to many and that the sites are somewhat related to your niche. If your two ways are coming from sites that Google likes and trust then you will not have a problem. Hope that helps.
Blog commenting is best way to build your back link . go to other blogs which type of your catagory. submit your site in google . send email with website url to who know you . you can use google adword to get quick response of visitors.
First if you can get good backlinks from authority site than one way links are best. But for relevant getting backlinks you need link exchange mean two ways links.
One way links are the best way to get better results for the site. As two way and three way both kind of links be known as the link exchange and it is suggested by google not to make use of link exchange method to get more backlinks to the site as it can be harmful for the site results. So one way backlinks are far better for all the results of the site as for the quality content, traffic and also for the relevancy.