There has been a continuing debate on the efficacy of Search Engine Optimization(SEO) versus that of PPC Advertising Management.
My two cents on the topic...
More visitors to search page are likely to click on these links than sponsored or paid links (we have observed that the ratio is 2:1) Since, this involves a lot of website tuning and making the website search friendly, the website that ranks high on organic listings(through SEO) normally has (arguably) a higher relevance and greater chances of conversion.
The long term costs are lower. The only cost involved is the (other than the obvious time cost) SEO consultation fee (typically, $50,000 to $200,000 for a 25 page SEO work). If averaged out over 24 months, this would mean $3000-$4000/month(average).
SEO takes time. Even the best SEO in business would take a minimum of 4-6 months to get your site up on the search listings for an averagely competitive category.
Ethical Search Engine Optimization firms: This again poses a big challenge to the industry. The ratio of ethical SEO's who know their trade to the unethical ones who indulge in unethical practices to get the site up in the organic listings, is 1: 1000!
Good SEO is NOT CHEAP - it CAN NOT be CHEAP: Typically, SEO means a lot of hard - continuous - effective work to get the site up on the listings. NO ONE can guarantee a position within a definite time period. Typical engagement fee ( annual) starts from $50k and depends on the number of web pages being optimized and the number of keywords these are being optimized for. Also, this is continuous work... it has to be, because of the regular changes that Google does in the way that it compiles and displays sites for keywords.
Pay-Per-Click(PPC) Search Advertising -Positives:
PPC is IMMEDIATE: The website ad can be up in Google sponsored links (https://adwords.google.com/select/) within minutes. In Yahoo Search(Overture) the ad is live within 4 days(max).
PPC is MEASURABLE: The click and the resultant action can be tracked back to cost,
PPC ad is more useful to an online buyer: The websites that advertise here pay to get listed. Normally, any website would do this only if they can SELL SOMETHING to the visitors. ROI matters.
PPC results CAN BE CONTROLLED: It's hard work - it's 24*7 work - however, it is far more controllable and predictable than organic listings. PPC impacts the "brand profile". This is a statement that is being tested for veracity. I believe in this because: If I am searching for widgets using certain keywords and one particular website's ads pop up for each keyword and when I click on the ad it takes me to the relevant location on the website... I tend to form a connect between visibility - relevance - usefulness - all these impact the website/brand profile.
PPC Can be EXPENSIVE if not managed well
PPC is threatened by CLICK FRAUD (something that can burn budgets very quickly if the campaign is not managed rigorously)
PPC space is very competitive and the bid prices are rising, literally every month
Only 1 out of 3 "search page visitors" are likely to click a sponsored link/paid ad
Like in SEO space, there are many firms that promise more than they deliver. Fortunately, the results are easily measurable and thus the ineffective firms can be sorted out.
I would not like to bias the reader with "what I think is better". Every business owner has a need - or at least should have a need - to get her site listed on the search engines.
Based on the pros and cons of SEO and PPC, it's up to them to make the decision.