DANI:
the ER's have wider wingspans
wrong
Only the 777-200LR and the 777-300ER have raked wingtips and therefore a little more span, maybe 1 or 2 feet extra each side?
All other 777 versions have the same wingspan.
SQ has 777-300ER's with raked wingtips but the a/c involved were 200ER's.
Besides, If you are that close as to worry about extra span then you should stop and get a marshal.