I feel that bars could be misleading insofar as they imply a continuous range of values and not just the mean. On the other hand, bars are much more noticeable for comparative purposes.
Secondly, here is a plot with means shown as horizontal "lines". They are likely more appropriate for showing a mean but I find it hard to compare the means and place the indivdual points with respect to the means by eye.
Here is the second plot:
If I would use the first plot in a thesis, do you think this will be found faulty, so to say?