Blog comments works and its still the most powerful method to rank a website.But.you need to find blogs which are relevant to your niche and have low OBL may be less than 30.Even if you dont get relevant blogs then make a comment in such a way that you can insert a link in the reply without making it look like a spam comment.FOr example,if you have ablog about bed bugs then you can make a comment on hotels related website and can make a comment like "have been to the hotel last year it was full of bed bugs,they should have some kind of solution to control this your site link ".
High PR blog comments with low OBL are still the best way to rank a website.
High PR blog comments with low OBL are still the best way to rank a website.