When everything goes digital then it is better to have digital documents too. Especially those certificates with high value as they can be required anytime and anywhere plus if lost then you have gained all the trouble of getting them back again.
Thus digital signature certificate are the new trend and support to all. It is a soft copy to your hard copy. That is very easy to get and store without any harm.
Digital signature certificates have their own merits and drawbacks like you can get a fake signature or you might never get what you paid for. So it is really important to find a trustworthy site which can get you the certificate without or less trouble.