Yes you can use T-rex blades on the #36. I have some Align ABS ones on mine currently, they are a cm or two longer than the standard foamies but work no worries at all.

Is the #36 good.... hmmm thats a curly question. They seem to be a bit random quality wise, you'll find them in AUS at www.rchobby.com.au for about $250AUD delivered. I would only recomend that you try and find a barebones kit or be prepared to through the electronics that come with it out and replace it all with quality stuff because there is a very good chance you will need to anyway to get it running reliably.

Flying with the brushed motor was a no go for my #36, the internal ESC overheated all the time and caused the gyro to reset mid flight. So you really need the brushless setup IMHO.

I'm still not sure if I would go with a #36 again, it would be better to go to www.wattsuprc.com.au and grab a T-rex kit, parts are cheaper and easier to get in Australia for the T-rex and Wattsuprc have the best customer service I have ever experienced with an online store! (I am not affiliated with them in any way, just a very happy customer)

There is no cheap way to get into the CP elictric heli game, save around $1000 and then go shopping for a heli, radio gear and a sim(Sims are dear but they pay for themselves pretty quickly. Plus G3 is good fun online to get help).

Hope that helps you make up your mind