Nexus 6 handset is more costly than Nexus 5. Nexus 6 mobile will launched with new Android Lollipop as well as features like 5.96 inch screen size, 1440x2560 screen resolution, 13MP rear camera, 2MP front camera, expandable memory upto 32GB. The Nexus 6 handset is good combination of latest operating system and robust configuration. According to my opinion, you should wait for Nexus 6. Along with this, I want to suggest you LG G3 handset. LG G3 mobile will give fluid performance with no lag.
OnePlus 5 review