Modified P90X question

Hey,

I have completed the first round of P90X, it was fun and all and I am happy with the results but I much prefer running and running. I love to do HIIT running! I created a new workout for myself, here is a sample:

Day 1 - HIIT, Ab Ripper X
Day 2 - Chest & Back
Day 3 - HIIT
Day 4 - Shoulders & Arms
Day 5 - HIIT, Ab Ripper X
Day 6 - REST
Day 7 - REST
——————————————————————————

My question is: The P90X videos above in my sample workout are an hour long or more. Could I do the first 30 mins of the P90X videos listed above in my workout and benefit or should I find different resistance/strength training parts of my workout? Keep in mind time is an issue and I do this all at home or when I travel. From what I read the first 30 minutes are the most beneficial to you so part of me thinks it's BETTER to do the first 30 mins hard and then cooldown.

Please help!