I have a quick SEO question guys - I've seen people do all kinds of weird things with link spamming and other black hat methods to try and inflate their backlinks and get better page rankings. I've also seen people doing link exchange or link purchases with PR2 or PR3 blogs and websites, and get some results with page rank as well.
I've heard of people that actually go for high PR links at major websites, but never done that myself or known anyone personally that was successful at getting links in that manner. My question is which method is actually the best - should you go for a large amount of medium PR links, spam links or work on getting the highest level backlinks?
Obviously getting links from major authority sites is the best, but what kind of investment is actually required to get those links and is it worth the risk that your project ultimately won't work out after you spend that money? Is the best way to get a great link simply by producing great quality content?
Any insight into the above would be much appreciated.