Hello
The best option is to not to enabe vtp.
1. it will avoid you from accident vlan erasing
2. vtp is one of the consistency parameters for vpc. As long it's not enabled it's not considere, but after enabling it devices will start to compare these settings which sometime may lead to type-2 inconsistency.
Also here is an example from my lab device:
N5k1(config)# feature private-vlan
N5k1(config)# feature vtp
N5k1(config)#
N5k1(config)# 2012 Jun 28 07:04:10 Podsos %DAEMON-2-SYSTEM_MSG: <<%VTP-2-VTP_MODE_OFF_PVLAN_EXIST>> VTP Mode changed to off as Private VLAN configuration exists - vtp[28032]
HTH,
Alex