As I understand it, EscrowDNS actually takes the domain into their possession (like Sedo escrow & Moniker escrow)...Whereas, escrow.com doesn't.
The difference could be that its hard to see how a scammer could scam a seller with EscrowDNS...
...but, with escrow.com, that doesn't actually take possession of the name, an unscrupulous buyer could receive the domain from the seller, then immediately change the Registrant info back to that of the seller - and claim to escrow.com that the seller never transferred the domain (using the (now) false WHOIS info as 'evidence'), and demand the refund of his money....thus stealing the domain.
The 'take possession' escrow services are therefore safer, imo.
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