No experience with the Nukes, but I haven’t had any Wordpress problems here.
Personally, I prefer not to use the one-click upgrade on WP, but it does work. If you use any themes, plugins, or code mods, you will need to redo them after a one-click upgrade.
For a standard installation without mods, it would probably be the easy way to go. Note that you will need to run the /wp-admin/upgrade.php script once it’s done. It backs up your old one before upgrading, incase there are any problems.
I just follow the upgrade procedure at wordpress.org and haven’t had any problems with mods/plugins/themes. It’s pretty quick and easy, so I don’t mind.
DH seems pretty good with security issues, so I can’t picture them blowing off anything for 2 days. If they actually did, I’d say that’s an exception.
For general support, they try to reply within 24 hours, usually much quicker. It can get a little backed up when there are a lot of signups, like when the Code Monster plan is half off.
Save up to $96 at Dreamhost with the 96DOLLARSOFF promo code.