I can testify to the change in response from a high end radio..
I started out with a stick Futaba attack II.. (Similar to a 2ER)
Switched to a Futaba 2PL. Not much faster, but more accurate. And much more solid feeling. No "hollow" components
Switched to an XS-3 By JR. WoW! Amazing difference, the whole radio felt like it was designed to race. The controls were adjustable for tension, lots of new features. Without it I couldn't have controlled a faster car. With the faster car small details are revealed that you wouldn't feel in slower catergories. It was not super accurate. It certainly did the job but the whole setup was a little slow.
Finally changed to a 3PK and a fast digital servo. 0.08s/60deg.
DAMN! Night and day.
With the 3Pk - just resting your hand on the throttle results in input. The smallest change in pressure shows on teh throttle graph. On the XS-3 there was a slight deadband around centre. You could rock the wheel back and forth a small amount without anything happening.
Ditto with the throttle - small changes in the throttle on the XS-3 didn't seem to do that much. The 3PK is smooth and linear. And again, the slightest change in pressure (without discernable tigger movement) resulted in a change in the car speed.
I found it quite hard to drive a fast car with a lesser radio now. You feel disconnected. But am I faster? yes - but I've also had more practice.
I do feel more in control and it's definately more intimate. It's more fun - and that's what counts!
(Go for whatever contorl suits you - I'm sure teh stick radio's are the same.)