Congrats on your first Vette! Hope you have many happy miles together!!
The car will run fine on standard unleaded as stated, but the ECU can detect higher octane fuel and switches to a different ignition/fuelling map. It will thus run better on E5 and if, as suggested, you use Tesco Momentum 99 [which is the highest octane fuel normally available in the UK], it is little more expensive than a big name 95 octane. The additive package for the 99 is also one of the best in the business and is really good at preventing problems liked clogged injectors. It's your car and your money, but I learned a lot of this when my car was remapped by a guy who has been remapping LS engines for the best part of 30 years and have used Tesco 99 ever since.