Rmasa,
If looking to replace your chain, the benefits of going with an ebike specific chain really makes a difference if you ride with a mid drive system. If you ride with a Bosch mid drive, there will be much higher torque being applied to the chain vs a rear hub system.
If you ride with a rear hub system then a basic chain will be OK. With that being said the less expensive parts typically are made from materials that will wear quicker and will typically get a shorter lifecycle then a higher quality chain. Now keep in mind that a cheaper cassette / freewheel will also be a wear point. So ideally you want to match similar qualities there to get fairly close wear patterns. No point getting a high quality cassette and throwing on the cheapest chain. With a high quality chain/cassette setup riders will typically experience longer life, smoother shifting and a generally nicer ride. Keep in mind that the whole drive train needs to be properly maintained and lubricated. A bent, dirty worn out derailleur wont make a high quality chain / cassette feel better... ;-)
Now, here is where I feel and know that an ebike specific chain makes a difference. If you use a basic chain like an HG40 for example on a Bosch mid drive then you're probably going to experience a chain snap at one point. This is due to the high torque being applied to the chain from the drive unit. If you have a great bike with a quality cassette for example and put on a basic chain like the Shimano HG40 you're probably going to spend more $$$ in the long run then dishing out the extra cost of buying a better quality chain. The accelerated wear will certainly eat away at the cassette and front chain ring much quicker assuming it doesn't snap before that. If you have a shop do your service work for you, you'll probably spend more in the long run then biting the bullet and getting yourself a decent chain / cassette set up. We have clients who use a good quality Shimano / SRAM cassette paired with a CONNEX / KMC ebike chain and also a CONNEX chainring and have increased their life cycle already to the point where we have not been able to determine by how much as the setup has not been due for replacement yet. I am sure they will be ahead when they calculate in the labor savings and I know they are ahead if they calculate their time for not having to bring the bike to the shop for service.
If you ride offroad and ride hard with a mid drive like Bosch, you need the best (chain, cassette, chain ring etc....) that you can afford. Trying to save a couple of $$ on a mountain bike when going offroad will just cost you more and ruin your day eventually. When you shift frequently under load this is really where a high quality chain like the CONNEX or KMC E series combined with an upgraded chain ring makes a difference.
In summary a rear hub is more forgiving than a mid drive so you can use pretty much anything. Ride more aggressively or want the convenience of getting longer life, upgrade to the higher end ebike specific components.
hope this helps,
Will
shop.scooteretti.com