Cons of upgrading to Windows Phone 8.1 (Developer Preview)

I own a Nokia Lumia 620 and i'm contemplating upgrading to the 8.1 developer preview.

I know i'm probably late to this party, but i would like to know what are the primary drawbacks of this upgrade.

Once you upgrade to a developer preview, do you get the regular (official) updates from Mircosoft?

Are there any battery performance issues? ( I know that Mircosoft has addressed their latest update)

Does this void your warranty?

Any help will be much appreciated.Thanks!