Adding the VHF dipoles is strongly recommended for improving the VHF reception.
http://www.antennasdirect.com/store/Reflectors.html
Either option will work. Currently, the VHF-1 Retrofit Kit has free economy shipping loaded in our e-commerce system. The VHF Reflector Kit is being phased out in favor of the module-based option and there are only a few dozen VHF reflector kits left in inventory.
VHF reception can often be disrupted by unexpected localized sources of interference. Sometimes it's a fancy new light bulb or appliance, a solar-powered device, a new computer, or even a new TV set or adding a plug-in USB device to a TV or computer. There are quite a few possibilities.