Warning Achtung Halt Iphonesimfree Scam!
After getting an email from these guys I looked up their message origine using WHOIS, here are my findings: They are based in Amsterdam, NL sounds really fishy!
Record Type: IP Address
OrgName: RIPE Network Coordination Centre
Address: P.O. Box 10096
NetRange: 184.108.40.206 - 220.127.116.11
NetType: Allocated to RIPE NCC
Comment: These addresses have been further assigned to users in
Comment: the RIPE NCC region. Contact information can be found