I've written a review of Ubuntu 15.04 Vivid Vervet 64-bit edition, tested in a multi-boot Windows & Linux setup on a Lenovo G50-70 laptop with UEFI, Secure Boot and GPT, covering live session, install and day-to-day use, including look & feel, network connectivity - Wireless, Bluetooth, Samba, partitioning & slideshow, software updates, applications, webcam, multimedia - Flash, MP3, HD video, resource usage, new Samba printing, performance, responsiveness, suspend & resume, stability, hardware compatibility with one outstanding bug with the Realtek Wireless card, Dash & Scopes improvements, customization, some other observations, and more. Enjoy.