That is hardly a choice. Working with Apple's Education support channel, they *instructed* us to to install the new Configurator 1.4 after 5 of our students installed iOS7 on their devices. Even though the devices are supervised with the app store removed, the students were able to instal the new iOS without any restrictions. Once iOS7 was on the supervised devices, any changes that needed to be made to the devices via the MDM we are using or via Configurator 1.3, were no longer functioning. We couldn't remove or add apps via either. We also couldn't bring the devices out of supervised mode. Strike 1.
Configurator doesn't give you the option to disregard new iOS versions, so as soon as iOS 7 was released, our Configurator installation saw a new version available, downloaded it and now locked us into only being able to deploy iPads with the new iOS. Contacted Apple to get a work around to have Configurator "forget" that the new iOS was out and fall back on the previous version. Apple refused to help us with that issue at all. Great. Strike 2.
We had to wait the 3 days it took Apple to upgrade their Configurator (gee, departments within Apple don't communicate huh?). The damage was done at this point to our test pilot of using iPads within our school. The confidence in the iPads among the students and staff has dropped considerably and it will take a while to get that back. Strike 3.