There is no data transfer cap for ILLs. We use You & Tulip.
1Gb port i mentioned, as we need high speed communication across nodes. We use Cassandra, Hadoop so internal data transfer rate is very high. So for internal communication 100Mbps creates bottleneck, but definitely sufficient for external communication / bandwidth.
I commented from what i got from pricing page. Apart from basic server cost, there's always associated extension hardware/data/software cost which generally makes it much more expensive.
If you have more details on cloud setup using Hetzner and associated cost, we would be happy to explore.
Hetzner can set up a private gigabit vlan upon request[1]. They charge a one time setup cost for the switch (30 euros) and 15 euros/month/server. Internal and incoming traffic is free. With this setup, internal data transfer is at 1 Gbps while external transfer is at 100Mbps.