I can tell you from personal experience that there there is no problems with using Electrum and ElectronCash wallets on same PC.If something was wrong with ElectronCash in first version they fix it,and for version 3.0 of ElectronCash I can say it work 100% correctly.What most people do wrong is that they download fake BCH wallets and lost their coins,some others lost also BTC because they using seed/private keys with BTC balance.
Can it be any issue with ElectronCash latest version and Electrum 3 versions maybe I do not know because I am not using Electrum 3 for now.
The only issues that they had, was that the first version made the somewhat ill-advised move to "copy" the wallet files from the Electrum wallet directory to the ElectronCash wallet directory... some people decided that this was "The End of the World"™ and cried ZOMGWTFHAX!!?!
(Note, this was a totally different issue to that of BitcoinABC which installed to the same directories and used the same datadir locations as Bitcoin Core, which lead to blockchain corruption etc)
The ElectronCash devs quickly removed this wallet copy "feature" after the backlash...
Also, there was a minor technical issue with ElectronCash connecting to BTC servers instead of BCH servers... this didn't pose any risks of BTC or BCH being lost or stolen, it just meant that it wasn't updating blocks correctly and was showing incorrect transaction info until the user connected to a BCH server and/or deleted their blockchain_headers and started again.
Lastly, they had some technical issues around MultiSig wallets that took a few days to sort out... it basically just meant any BCH on a MultiSig wallet was unable to be moved... Not really a huge deal.
Since then, I have personally had ZERO issues with running ElectronCash and Electrum 2.9.x and 3.0.x on the same PC (even at the same time)
Thanks for sharing guys! Very cool elaboration by HCP.
It seems like the minor technical issue you mentioned happen on Electrum for BTC as well before 3.0.x. I'm on 3.0.3 currently by the way. Occasionally I'm connected to the BCH server despite using Electrum for BTC.
Is there a reason why you are not updating to or beyond 3.0.x? 3.0.x has segwit while the earlier version doesn't right?