If you are trying to save money, your in the wrong hobby. If my budget is $2500 I'm going to spend it all and then some every year. It's only a matter of where else I'm going to spend it.
I can give you an example. As an owner of the Novak Supersport SS, Novak GTB, Sintered 6.5 Velocity, and soon to be owner of the newest generation of Novak Brushless system, I have not really saved any money by switching to brushless. I've probably spent a lot more than if I just bought a GT7 and stuck to brushed motors 3 years ago.
Isn't it weird how about every year or so there a new motor or system hits the market that makes my current brushless stuff obsolete?
The same thing will happen with Lipos. This is just the beginning. New stuff will keep appearing and you will be replacing your entire battery collection every year.
Instead of buying 6 4400 NiMh batteries for $45 each = $270/yr you will be buying 2 4800 Lipos at about $125/ea x 2 = $250/yr.
I would be willing to bet that Orion is already developing new Lipo cells that will perform better than the ones the made last year. I actually don't really have a problem with that. That's what its all about.
I like lipos for the promise of better overall performance
I don't like them yet because there is not enough manufacturers joining with Orion to design and make batteries specifically for RC cars.
Saving money is not really even in the equasion for me.