It really depends on what you would like to do with your Phone. For me, until there's no OpenVPN client support I deem it necessary.
Connecting to to the Office network on the go and being able to administrate some servers or connecting to Terminal Services is great and gives me such freedom. On the private side, it's awesome to be able to load my iTunes library from home on my phone - wherever I am - and listen to audiobooks (which I do a lot). Since iTunes match doesn't match audiobooks my VPN is the only way to access them on the go natively in the iPhone Music App.
At the moment I hardly use my company-issued iPhone 5 because I'm not able to VPN in to the company network. Instead my iP4 still gets denied retirement...
Also SB-Settings is a real time-saver and Glasklart makes the icons less eye-hurting ;-)