co vs com domain name
.co are new upcoming domain name extensions. .com are very old and most popular extensions. Hope everyone will prefer to go .com domains instead of .co since it was familier.
My site is etechtricks.com and you bought etechtricks.co. You increased your traffic and got some good amount of visitors then I too will get some visitors of your site. By miss typing or miss understand.
So I always prefer to go for .com domains.