Yes. Most research seems to support the basic claims regarding mindfulness: facilitated meditation has a positive impact on stress indicators, and reduce the incidence of depressive episodes in those with chronic depression.
Mindfulness does not directly remove stresses and pressures from your life, but it does allow you to concentrate your energies more effectively, and to understand your life more clearly.
Mindfulness comes in many guises, and the same principles are applied - using different vocabularies - in professional disciplines such as sport ('being in the Zone') and drama ('being grounded'). Pretty general consensus: it works.
Most of the evidence about effectiveness is anecdotal of course, but for those of us at the chalkface, that is pretty-well what we want and need: we want to be able to say we feel less stressed; less exhausted and less on-the-edge; and more in control of our lives.
Mindfulness might be effective in developing mental health, but improvements are not always quick or dramatic. There are no euphoric revelations or states of bliss. It is frequently described as a journey or a process, not an instant remedy. It is frequently used in tandem with cognitive analysis, and in this context it can be unsettling, as it requires us to understand our painful experiences and face up to real problems without distractions or diversions.
To be effective, Mindfulness does need to be practised over time, and therefore requires some discipline. Having said that, in a teacher's hectic life a little tranquillity goes a long way, and many find immediate benefits. Having said that, meditation cannot realistically be expected to offer a cure for all aspects of the human condition. Having said that... no, I think you get the point. If your expectations are reasonable, mostly, it works.