The two FARICE submarine cables and the Greenland Connect carry Iceland traffic to mainland Europe with around 18-22ms of one-way latency to London and 30-40ms to Frankfurt. For SIP signalling that is well inside the budget needed for sub-30ms jitter, the threshold below which G.711 audio sounds clean. For New York reachability over the Greenland Connect, count on 45-55ms one-way, again fine for voice.
The peering side is thinner than Amsterdam, so check your SIP wholesale carrier reachability. Some Tier 2 SIP carriers route Iceland traffic via Stockholm or Frankfurt, adding a hop. We document the carriers that peer cleanly at RIX (Reykjavik IX).