I have actually fished both the WT and the Boron IIt fly rods, and I think that both of them are great fishing tools. The question you have to ask yourself is which one is more effortless to cast. That is the rod that you should choose! When I am looking for a new rod, I spend at least an hour throwing them side-by-side. I take some different line tapers(WF/DT), and I try to throw them into any kind of wind. That is something that alot people don't do, and it is something that you should always do. You need a rod that can do what you want it to do, and do it in any condition.
Another way to compare rods is to set up targets on the lawn at normal fishing conditions, and cast at them. Your average fishing cast for trout is going to be anywhere from 10'-40', and you need to make sure that the rod you pick will get the job done for what it was designed to do. Too many people get out on the lawn and try to huck it as far as they can, and I always have to tell them to make the casts that they will use on-stream. Honestly, it comes down to your opinion, and no one elses. I love the fact that Boron IIt's are so light and easy to package, it makes a big difference when you are on the go, and they are essentially a WT...but much better. That is my opinion, and you can take it for what it is worth, but I know that the WT series is still a very good trout rod. I hope that this aids you in your decision-they're both awesome rods. You can't go wrong!