locky

The XMaxx/ XRT is smaller I  but more importantly, much much lighter. The weights the issue. Weight makes it awkward to transport, you need lots of power to get decent speeds and as a result of that if its electric you end up with single digit minute runtimes. Then if it breaks in a middle of a field you have to lump it back to the car/van or hook a dog lead to it and drag it. 

Traxxas smashed it with the XMaxx/XRT mainly because its all plastic. Its so light for its size it just means you get much more run time and performance out of them compared to a “proper” 5th Scale. 

I used to transport my HPI Baja on a motorcycle....and to do so, I built a frame/carrier that bolted on where the grab rails were, and attached it to that. Then used a dog-lead to tow it to wherever.
The things are heavy.

For more local carriage, I had a sack barrow truck thing.

I'd never give up my fifth scales, just too awesome when driven hard. 

My runtimes are fair, but that's because I run low kv on high voltage. Not cheap, but more efficient with the available power. 

Keep in mind that the true largescale machines aren't really made for big air, best kept long and low. 

The large Traxxas machines are a viable option for large scale fun, with a few choice upgrades. (But I haven't owned one yet!)