Just because items are more expensive does not mean they wont break. I have been at this 10 years and still do not own a digital servo. No need for it and I have some nice planes. Money may or may not be an issue with you but right now, your wasting it

If you have basic good flying skills, your not going to be able to tell the performance difference between a regular servo and a digital when it's in the air so why spend the money. What kind of radio are you using. If youwant to collect things for the long run, make it the support equipment like starters, tachs and stuff. Those things generally last much longer than the average plane