I actually disagree that consumers aren't aware about which SSL cert is being used. They may be registering it subconsciously but research has shown that people react well to the green bar and conversions are increased. People are used to seeing it now, especially as online banking has exploded:
Taken from http://www.verisign.co.uk/static/EV_DataSheet_UK.pdf
In January 2007, Tec-Ed researched usage and attitudes of 384 online shoppers and measured their responses to Web sites with and without green bars:
- 100% of participants notice whether or not a site shows the green EV bar
- 93% of participants prefer to shop on sites that show the green bar
- 97% are likely to share their credit card information on sites with the green EV bar, as opposed to only 63% with non-EV sites
- 77% of participants report that they would hesitate to shop at a site that previously showed the green EV bar and no longer does so
If you forget the functionality of the type of cert to begin with. The lower end certs technically do more or less the same job as the more expensive certs. The thing to look at here is building trust.
As mentioned, pretty much anyone can get say a RapidSSL cert, if you purchase an EV then they for a starters cost more and the verification process checks that the business is legitimate (they check contacts, VAT numbers etc.). Both of these are likely to indicate that the owner is in it for the long haul as they have made a much bigger outlay in the first instance and have gone to the effort of creating a genuine business, it tells the customer that they are much more likely to be around in say a year and not gone tomorrow. The cheaper certs are adequate for many things but particularly if you are looking for someone to trust you with their bank details then I would suggest an EV cert, especially for a new business.