I like the Blade 400 or Blade 450.  Like you noticed almost any LHS has parts to fix them and they do not cost much to repair.
If you want to buy new go with the 450,  but you can probably find 400 used for a good price.

Bigger heli's are easier to see and fly.   If you have been flying the Blade CP you are much better than most people I know who tried to learn with that one,   and you will like the 450 so much better.   

Don't be put off if the 450 heli says 3D on it, any heli can be dialed down to fly easier.   The Trex 450 is a great machine but it cost more. The Blade 450 is good and you could upgrade it to perform very near the Trex's performance.   You would probably put as much money into the Blade machine as is in the Trex from the start.   

IMO getting spare parts is more importaint so find out what your LHS sells.

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