Electric Assist

After five long distance tours across the USA since retirement, I'm doing research for this year's 4,400 mile adventure in the electric assist motor kit realm for my REI Novara Safari. I'm 73. I can get away with it. I don't see any problem with not being a purest, not when I have to cross the Great Smokey Mountains, the Rockies, the Cascades, and the Sierra Nevada's, all on one ride. I'm tired of pushing up steep grades, and it burns up so much time. From what I have gathered so far, there are models that can be used on either wheel. I'm looking at a front wheel application, only because I have finally gotten my rear wheel just right to handle all the weight with extra spokes and heavy duty rim. If it works, don't mess with it. The electric assist companies make great claims of distance and speed. If I could find one that actually produced only half their results, I would be thrilled. I understand that these setups are for the 'commuter' market and not touring applications. I have not found a manufacturer so far that is confident enough to recommend their product. It seems to me that if a 'commuter' product made it all the way from ocean to ocean on a loaded bike, this would speak well for durability and quality. A go-getter should jump on this. ...Are there any ideas out there to further my search?