I have both a Trex 500 and 550 DFC.

I really like both of them, I have the 600 boom and longer blades on my 550.
Both are controlled by Bavarian Demons (the 550 is actuall a Heli Command).

I can't say say that I really like one more than the other. Both are big enough to be pretty stable, as far heli's go anyway. Both fly well, cost of maintenance and repairs if needed isn't much different between the two.

Battery cost is different though, batteries for the 550 are much more than for the 500. At least for good batteries.

The 550 is a bit more floaty, while the 500 feels a bit more nimble. The 550 is a bit easier to see.

The big difference at least for me is the "pucker" factor. It took me 5-6 packs to get used to the 550, another couple to get used to it. Probably only 1 or 2 for the 500 and it felt good.

My largest Heli prior to he 500 was a Trex 450 Pro DFC. I bought my 550 within 2-3 weeks of buying and building my 500.

Either would be a good step up from the 450. Of I had it to again though I would skip the 500 and get the 550.

All that said, it's been a while since I've flown any of my heli's (I have 9 of them) I've made the decided to get out of heli's and will be selling all my heli's and related equipment in the next couple weeks.

Of anyone might be interested in some very well maintained heli's (I'd rate all of them 9.5's-9.75's out of 10'd) none of them are stock, all are well upgraded none with the exception of my 500 have been crashed.

The 500 had a minor crash from a low hover due to a brown out and was completely rebuilt.

Anyway, if anyone ipmight be looking for some really nice heli's reach out to me by PM.