You did ask, so there you are :-)
The feeling of having the "urge" is exactly the same as before for me, it is located where the bladder is and slightly below.
But when I start peeing I do not feel the warmth of the liquid ascend through the male anatomy any longer, I am consciously aware of the MUCH shorter urethra and the location of the new opening every time. The next thing I think then is "have I waited long enough so that my labia minora have become unstuck?". If I have (and they have), there will be happiness and a clean, straight spurt going down right into the bowl. If not, there will be a nice warm mess all over typically one of my upper thighs and the associated buttock.
For maybe six weeks after my SRS I had to get up and pee two or three times literally every night because my bladder pressing on something caused me considerable pain even if it was not really that full. This has now (almost 4 months post SRS) reverted to the behaviour I have known from before, if I drink too much before going to bed I may wake up a few times and feel uncomfortable because of it, but I can hold it until the morning.