3 nodes each with:
first gen i3 cpu, 4GB RAM
Ubuntu 12.04 Os is installed in a 8GB flash drive
all gigabit interfaces
eth0: 10.2.0.0/24 network for cluster
eht1: 10.1.0.0/24 network for public

Each node has 3 OSD:
3x1TB Drives, I tested their raw write speed of a little over 100MB/sec
Journals is on the same drive as the OSD. NO SSDs are used.

Here is the test i have done for ceph:
Mounting a RBD and perfoming copy inside the RBD folder
Command will write a 1GB file:
    dd if=/dev/zero of=here bs=1G count=1 oflag=direct
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 33.4544 s, 32.1 MB/s