I am not a fan of timed quests when I am playing a game that throws quests at me left and right. In the early stages of these games I can have 10 to 15 quests in my Journal that are ready for me to do something. So, I am working on one of those quests I already have, and bam, I have to drop what I am doing to go deal with this issue or doom will happen. I hate timed quests so much that in Oblivion, I just go TCL and walk across the plane to the final tower bypassing all the other ones. Did it the way I was supposed to the first time, but never again after that.
A timed stage in a quest that I am involved in at the time, that could be OK. For example, the last part of Dead Money, even though I hated that part of the DLC and it is the reason that I have never finished Dead Money with any of my characters in that game. In fact, I use a mod that skips the whole DLC.
I also hated the time limit in Fallout 1 for the MQ. Now, that is not as open world as later games, but it did curtail exploration of what there is.