I feel stronger and much more supple. Get less aches and pains, flexibility greatly improved. Also feel mentally stronger and more relaxed.
 More relaxed when dealing with attackers. Unlike other martial arts, Sifu Waller's tai chi is extremely pragmatic with regards realistic attacks.

 The training is friendly and relaxed yet still effective. There is no pressure put upon the individual. You train at your own pace and progress as you wish. Everyone in the class is treated the same, there are no favourites or cliques like most martial arts classes.

 (Paul B) 

The student as a boxer, not a fencer.
 The fencer's weapon is picked up and put down again.
 The boxer's is part of him. All he has to do is clench his fist.
 
 (Marcus Aurelius)

We want to scale the steepest cliffs to lofty heights.
 But forget about ambition;
 get on with the work of climbing,
 this is what the sages tell us.
 Vinegar has its own sweetness.

 (Loy Ching-Yuen)

Beyond intention

When a person attacks you unexpectedly, you cannot have a plan in mind. You must simply respond and move appropriately. This is a condition that transcends intention.
Intention may be present insofar as you have no wish to be injured, but beyond that there is no fixed plan. The event happens and you are part of that happening.

Concentration?

Intention is not concentration. You are not narrowing your field of focus. It is quite different to that. 
Your gaze must remain expansive and peripheral, with the eyes receiving information rather than seeking it. Intention is the beginning of the movement, the middle and the end.
It is the way of the movement, the process. Do not mistake intention for planning. You must remain adaptive, flexible, changeable - preconceived notions are not the Way.

Broadcasting yourself

The need to broadcast stems from insecurity. By marketing your lifestyle and accomplishments you are seeking approval and envy.
If you seek attention, you will find it. But attention-seeking is less about courage than insecurity.
A person who dresses or acts to court attention is not bold; they are lonely. They want to be noticed. Their performance is intended to seduce you into adopting the role of audience.
Resist the urge to parade your accomplishments. Showing-off only attracts unwanted attention in the form of jealousy and resentment.
Chuang Tzu argues that it is foolish to advertise your wealth or your fighting skills.