I test rode a pace 350 and 500. Between the two I'd probly take the 350, and buy a higher end mountain bike in addition. Like a Haibike with Yamaha mid-drive.
For any cheap bike you have to be able to MacGyver the thing together to keep it running - juiced or radpower or whatever flavor of the day. You are more or less on your own. The Aventon isn't a high-end bike, but surely works as built. Your warranty is only as good as your dealer.
If you buy a high-end bike from a LBS you can trust they'll keep it running for you. YMMV
There are a metric-ton of new startups in the ebike biz. Some will not be here tomorrow.
The hub drive bikes are very simple - power drives the hub. The mid-drive bikes with all the sensors are much more like actually riding the bike. We have both, and both work well, but the higher end yammer drive is much smoother and gets better range on less power - it only pulls when you pedal. There are pros and cons for both.
For a couple of hun more on your budget you can get a Giant or Yamaha mid-drive that is smooth as silk, or for five hun more a really nice Trek Verve. All of the higher-end mid-drives are very nice to ride. It's easier to find a really nice bike for a little more than to try to find the bottom of the market.
Go try them all and then decide. After a few years the difference in initial cost will be meaningless. And there are some really good end-of-season sales going on, a good chance to pickup a steal-deal - actually get more bike than you thought you could.