Sorry for the VERY late response. I was searching for unique training questions and came across yours.
"Supposedly this shoe gives more return than a traditional running shoe. If so, running a certain distance at a certain pace would be "easier". Does this mean you are getting less out of training? Also, does it make it so when you do switch to a traditional shoe or into racing flat/spike that you get less response and it becomes more difficult to run/race?"
Since you are able to run a given pace with an "easier effort" you will most likely increase your pace or distance (On a training run with no set requirements). Thereby, you will also be expending the same amount of energy and therefore you are getting the exact same out of training (assuming you are using the exact same amount of energy). Furthermore though, if you are able to run faster or further you are getting an EXTRA benefit as your body is getting accustomed to the enhanced pace/distance (fast twitch muscles are firing more. Thus getting larger and/or slow twitch fibers are being elongated)
"I love the feel of the shoe but as I am in training for my upcoming xc season, I don't want to get less out of the training I do or make it so racing is in fact more challenging because I have become accustomed to a more responsive shoe."
The EVA or PU in a spike has much lower duramtor than a training shoe with EVA/PU or the new Boost material. Thus they will be more responsive always.
A road racing flat varies by type. It sounds as if you are in school and therefore running 10K and below. I would imagine the flats you use will always be more responsive (as compared to a marathoner who would need more of a balance between responsiveness and cushioning)