Can't decide how I want to complete my evelynn lane build

Both builds primarily focus on attack+penetration with the last 2 items in question.

Build 1:

1. gauntlets
2. mercury treads (sometimes tabi)
3. black cleaver
4. last whisper
5. botrk - for some sustain, on hit, slow, and synergy with armor pen
6. ga - for defense and rebirth

Build 2.

1. gauntlets
2. treads
3. cleaver
4. whisper
5. zhonya's - for armor and invulnerability
6. banshee's - for health, mr, and spell shield

the damage of build 1 depends on enemy composition, but provides a small amount of health sustain and a speed steal active.

Build 2 offers a different means of defenses, with zhonya's cd being much shorter and user friendly than ga, and banshee's shield making engages safer.

I'm leaning slightly towards build 2 because it seems a bit safer, but also know the potential of build 1.

i'm open to all suggestions thanks.