Well I laid a full size M&P next to a Gen4 G19 and liked the size of the G19 better. To me the important part of conceal ability is the grip height. As previously stated the M&P has the same height as my 17. I did like the feel of the M&P a little better, but must admit was more familiar with the feel of the Glock. I also agreed that the M&P felt a little slippery in comparison. I have a 26 and a 17 (both now for sale!) and both have been flawless so I went with the Glock. I also don't have to get all new holsters and mags and stuff so I am happy with that as well. Will break in in with IDPA this weekend and let you know what I think. As long as it works, I am sure I will be happy.
BTW the M&P in the shop did not have the trigger reset click. Thanks for your help everyone.