Insulin Pump dillema - which one to get for my child?

I currently use a Dexcom g5 for my 7 year old son. So far we have loved having it - great to look on our phone anytime of day and see what his level is, really gives us peace of mind.

He has had type 1 for several months now - we were doing ok with shots for a few months when he was in the honeymoon period, but now that he is coming out of that giving shots 3 - 6 times a day for each meal and snack is just no fun, and of course there are the wide swings with shots. I would really like for him to get on an insulin pump soon to help even things out, plus he hates getting shots of course being a kid.

I want to stick with the Dexcom though - thinking of getting the x2 slim since it seems to be integrating with the Dexcom 5? Have also looked into the Medtronic 670, tempting but seems to be unsafe since he still takes a smaller amount of insulin. Thoughts, suggestions, what do you guys use for your children that works? Also have to think long term since this needs to last 4 years!