Hi Will ...
Glad to have you with the forum. I'm did basically the same thing; build a while, quit a while, build a while, quit a while.
I have used ModelFlex only once, and that was enough for me. I did not have good results from it. I tried it because the hobby shop I happened to be in at the time didn't have Tamiya or ModelMaster in the color I needed. Based on that unhappy and limited experience I'll be glad to help if I can.