As a sole traveller on a recent trip (having booked more than one year in advance) I was "permanently" roomed with one of two other single travellers.
I believe ImTrav should revisit its policy on roommates as other companies state:
"We room solo travelers (of the same gender) in a room together, usually in pairs and on rare occasions in triple bedded rooms. We rotate roommates throughout the tour when there are multiple solo travelers and your guide will do his or her best to make the room assignments as fair as possible."
After much discussion the three solo travellers went to the tour guide and ASKED to rotate!! It should be a given that no one person benefits by booking "last" and as a result does not roomshare. Thank you.