What about AtomicDEX?
https://atomicdex.io/ I've read a lot of positive feedback about it. I haven't tried doing swaps yet, I'll be trying it out soon.(Since it's in open beta now)
I seriously doubt it
To do an atomic swap, you need wallet software that writes a specific transaction script to make it happen. Unless that website is for such wallet software, then they're just using "DEX" and "atomic swap" for marketing purposes
and if so, they are lying. if the name of the website is a lie, you can't realistically expect that they won't lie about other things too
As was mentioned above by trucie months ago, Blocknet has 100% real atomic swaps on their Block DX exchange (requires full nodes in order to create and verify the transaction scripts you're referring to for now... a lite client is currently being developed though that'll leverage the XRouter network to do this vs full nodes).
For example, here are some links where you'll see the movement of funds to and from the p2sh addresses that are created as part of the atomic swap algorithm:
LTC (order maker) traded for BLOCK (order taker):
1. Maker deposits LTC into p2sh
https://chainz.cryptoid.info/ltc/tx.dws?36986143.htm2. Taker deposits BLOCK into p2sh
https://chainz.cryptoid.info/block/tx.dws?2476278.htm3. Maker spends BLOCK from p2sh, sharing secret
https://chainz.cryptoid.info/block/tx.dws?2476283.htm4. Taker spends LTC from p2sh with secret
https://chainz.cryptoid.info/ltc/tx.dws?36986148.htm