ORIGINAL: CGRetired
The only objection I would have to something that large would be the expense of all the accessories needed.. larger more powerful servo's, multiple batteries, larger fuel tank, larger gas engine (expensive in itself), and so on. All this can really add up when talking a plane that large. But, if money is no object, then, sure, that might be a good choice.
DS.
You forgot to mention that you also need a big vehicle to transport these planes to the field. It's pretty hard to put a 40% Extra 300 in a Honda Civic. Also, you need to consider the preflight foreplay, assembly etc. The nice thing about something like a Mini Ultra Stick is that you can throw it in your subcompact car assembled, stick a charged battery into it, and do a couple of flights during your lunch hour.