I suppose my answer could be refined as:

o If you need an ATM solution, use the AIP card.

o If you merely want a DS-3 or slower point-to-point link between two routers, test both solutions, (or talk to someone who has), to determine which solution has better performance; or

o If you want a point-to-point connection between two routers at speeds faster than HSSI can support (a bit more than 45 Mbps, I think) use the AIP card.

Again, you should also consult your router vendor. They should be giving you all this information and more. For example, you might discuss a OC-3c IP over SONET solution for point-to-point connections. -tjs

I would suggest the POS card over the AIP card for a local-interconnect.... -Peter