Lifeboat ambush

Have you ever tried this novel method of tackling the search party that flies in at the start? After triggering the dropship, nip back into the lifeboat to hide. Wait for enemy troops to approach or pass the exit, then ambush them. For example you could welcome them with a well-placed frag grenade lobbed out the exit, then rush out and drill the remnants with your assault rifle. It's not bad for a bit of fun, but on the higher difficulty levels it's admittedly far safer to wipe them out from distance.