Flow Flites should be taken for what they are... entry level bindings. They have the bare minimum because they cost the bare minimum. Okay, Flite 2s so they cost above minimum
With that said, my first pair of Flow bindings were Flite 1s. They lasted me a full season of heavy shredding. That was in '06. My brother in-law has been using them since and they are still working fine. Does that mean your particular bindings will last as long? Who knows. Maybe your kid is much better than me and jibs and stuff.
If you still have a chance to return them for something better, then do it. If budget isn't an issue to you, look at the NXT line of bindings.
My two favorite Flow bindings are the NXT-ATSE and NXT-FSE. I ride the FSE's and they are awesome! Light and very solid construction. I have one season on them so far and not a single problem. Actually, I did have a problem. My boot caught the strap (boot's fault, not binding's) and it caused a tear.
Also, after you order your bindings, you can call their customer service and request spare parts. They will send them out quickly. With my strap problem that I mentioned above, Flow sent out a temporary pair of straps promptly and then sent out the actual FSE straps when they got it in stock. I now have three sets of straps and extra hardware
The M9 should be your starting point for Flows. Anything above that will be even better. M9, M9SE, M11, NXT-AT, NXT-ATSE, NXT FSE. The SE versions are easier to set up because they utilize two ratchets instead of four. The two inner straps use a tool-less adjustment system similar to traditional bindings.
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