We have 2 7200 (NPE-G2) hubs and about 100 2811 spokes connected to each hub with one tunnel over an MPLS cloud provided by the ISP.
On the tunnels we use GRE+IPSEC
We have noticed that a lot of eigrp neighborships go up and down during the day while others are more stable.
Should we increase the EIGRP hello and hold time interval? It's the default 5secs, but since these are 256kbps links I think it should be increased. What do you think? (the spokes will become 200 soon)