open source or bespoke for a new website?

[susanna]

I need to create a new ecommerce site as my present one does not offer much flexibility and uses very old php and MySQL. What is the best software to use for the shopping cart; that is easy to use and offers many back end options or is it better to have a bespoke shopping cart which may be more flexible in the long run?
I would need to migrate all presnt products over (400+) so again this needs to be easily done and I would not want to lose present ranking on Google.

I am getting co***icting advice re. shopping carts - have been recommended Magento and osCommerce, while others are saying to go totally bespoke.... but I've also been told that Magento is very complicated and not easy to use for someone who doesn't know much about websites! Cre-loader has also been recommended as better than oscommerce but others are saying go bespoke as then you get exactly what you want.

Any advice would be most welcome!

[Corrosive]

I'd say it depends on budget. If you can afford it then go bespoke with a reputable web dev company. If you can't then I use Magento and Prestashop as far as Open Source is concerned but people will always have THEIR favourites and they may not always suit YOU