If you have a local dealer, you should be able to try out different models especially since Currie has many different types of ebikes. One thing that I had a problem with was the weight bias on a bike with rear hub motor and rear mounted battery, but that may be just me.
Some DIY kits are quire intuitive and don't require a great degree of ability to assemble; not a bad idea if you already have a bike that's comfortable for you; some, like BionX, are installed by a dealer.