mail is received with big delays (30 mins)

mail is received with big delays (30 mins)

Hello 
One of the biggest and obvious issues with Zoho Mail is that new mail is always received with important delays. From my tests Zoho receives new mail about 30 mins after it was sent. 

If I subscribe to a new mailing list using Gmail, I receive the confirmation e-mail in about 2sec. If I subscribe using Zoho Mail, the confirmation e-mail would invariably arrive ~30min late. 

Another test case is e-mails received from mailing lists. If in my Gmail account I receive an e-mail now, in Zoho Mail it will arrive in ~30min. 

I would like to switch from Gmail to Zoho Mail since it is the most promising alternative, but unfortunately this issue (and another 'refresh' problem reported in a different thread) make me question the reliability of your service. The first time I tried Zoho Mail (in Jul 2010) this very issue put me off from a switch. I'm a bit disappointed that half a year since this bug is still well and alive. 

Is this a known problem? Are there any plans to address it? Thank you
Liviu