Just wondering if they work and how long they usually last

Depends if they are rebound or lust or actually a real attraction to each other I would think.
I have heard of them working.

Let me answer it by pointing out that there is nothing any more or any less special about transitional relationships or rebound relationships or first loves or second crushes or any of that.

In the end, they all describe relationships that end... for one reason or another. The fact that they have a cute title (transitional, rebound... ) in no way makes them less likely or more likely to fail.

Worse, remember that ALL relationships fail. All of them. Except the last one (hopefully.) So, regardless of how you get into a relationship or how long ago your last relation was, the one you're in NOW has exactly the same likelihood of succeeding as it ever would.

Success is based SOLELY on meeting someone you're compatible with in all the important ways, and that, too, often has little to do with love.

So, don't worry about whether this guy came along too fast or not, always give every relationship your absolute best, but when it's over, don't prolong the agony... it's over.

They're ALL going to end, so try to make it as painless as is possible under the curcumstances. When the "one" comes along, it could very well be right on the heels of your last breakup, so don't miss it.