The only downsides right now is the initial sticker shock of the electric stuff, but once you get invested into a system it gets much, cheaper to expand.
Oh I'd also recommend buying a tool (with battery) from Amazon, having it get lost by UPS (actually an Amazon labeling issue), getting a refund for said lost item, buying the replacement at Lowes, and then 4 weeks later having the Amazon item show up at your door completely unannounced after Amazon had declared it officially lost. Got a free battery that way (and an extra string trimmer).