Whenever i do Link exchange , i need to give same PR link because everyone says good PR good power but some times i got the backlink from 0 pr page.

What u think about PR?
PR is important for LE or not?

I i do believe in Page Rank .But that sites should be relevant to your links and having a do-follow attribute.

I think link exchange from same PR or greater pr link is good but relevant site with less pr link than it is ok.

Having good page rank depends on variety of factors like domain age, size of the website, quality of content, referral links form other websites and other factors. So with concerning your own site, you don't need to worry about PR as I have seen many website which has high PR but low ranking and traffic so it is not necessary that having good PR would always turn into good traffic and ranking.

On other hand, having good PR is sign of authority by Google so when choosing website for promotion of website through SEO, you can have a look at PR.

Yes PR is a big factor for link exchange because if we get backlinks from high PR websites then we can get good improvement in our website SERP.

Yes, high page is very important for a website because it is helps to make good trust between visitors and your site. Most of visitors are think that high page rank is good for them and all web-masters using high page-rank sites.

Yes i believe in page ranking..