I like it a lot, it's one of my favourite Arthurian names - delightfully clunky, and with associations ranging from saintly to villainous. I pronounce it somewhere between GWEN-ə-veer and GWIN-ə-veer. Guinevere > Jennifer, a thousand times.
masculine list:
https://www.behindthename.com/pnl/191050/124079feminine list:
https://www.behindthename.com/pnl/191050/124080