I have always benched by myself. Sometimes for the last set, if I feel like I am struggling, I will ask somebody in the gym to spot me for one set - making sure they know not to touch the bar unless completely necessary! If I can't get a spotter I err on the side of caution and might not attempt that final rep.
I have been caught under the bar before and had to do the embarrassing roll off. Wasn't that awful, so I don't panic if I do get caught under the bar.
Basically if you can't get a spotter, be cautious but don't panic if you do fail on that final rep. You'll still be able to get the bar off you. Stay away from the Smith machine!


