Transcender is good, I also like techexams.net and the one I mentioned before, actualtests.com. They are all close to what the actual questions are going to look like so it will prepare you the best for what you might encounter.
I haven't run out of time on any of my tests thusfar...my norm is to have about an hour left, and that is with reading over the questions very slowly and calmly and with writing out any that I'm not sure on. Don't get me wrong, there were only a couple that I wound up having to write out as I only had a couple, maybe three, that were big long one's for permissions; on the rest I maybe had to make a couple notes to see if I was getting things straight. It's not like you're going to have to write an entire novel ;-) You'll just be writing down the names of the people or groups they give you in the questions, etc. and trying to put them in the correct place. You could even practice doing that with the transcender or actualtest questions if you wanted to so that you get the idea. There are a lot of things that you can do to prepare.
The main reason I always like to suggest that people look over the practice tests is that it helps you to not be blindsided by what the real test you're going in for has. If someone isn't prepared for the way Microsoft writes some of their questions they may wind up getting pretty confused, but if you know the material, look over the questions, etc., get a good night's rest

, you should be calm going into it, and as long as you don't get worked up when you're in there if you see something you don't know or remember, you can just come back to it....like I said, you may see another question that might remind you of something, or you may be able to sit and think about it and do process of elimination.
Process of elimination was something that was big on the tests I had to take in the military and has actually helped me a lot on Microsoft's tests. Most of the time they'll give you two answers that really don't make much sense (and Microsoft seems to do this too), and then they will give you two answers that are pretty close and seem like they might fit...they might have similar wording, or they might both seem to be possible, but if you really think about the question and what they're asking you, you'll realize that one is either the MORE CORRECT answer, or one just doesn't fit at all. They really will get you with that, but you have to just be smarter than the test. That is one more reason the practice questions are good. I know some people think that it's cheating, but I really just don't think it is. There's no way to remember 400+ questions by heart unless you're some kind of super human. It's simply another means of preparation...to get your mind in that way of thinking, to know what types of questions they might ask, the subjects you need to look over, etc.