All the more important to learn the right feel so you do not overcorrect. Most (all?) new flyers tend to overcorrect and it is important to learn to anticipate the plane's reaction so your inputs are just what is needed. Expo is helpful for planes that have extremely large control surfaces. If you don't learn to fly more conventional set ups without expo, you won't have much chance to succeed with more advanced designs even with expo.

So, expo can be a tool or a crutch. It's your decision.