I just had to switch from Vyvanse to Adderall XR because the only pharmacy in my area that didn't have a backorder closed. It's only been a couple weeks but I greatly prefer the Vyvanse, however the Adderall is better than being unmedicated. Adderall isn't as "smooth" and it gave me a tummy ache and caused headaches due to inadequate hydration. Since I figured out the hydration issue the headaches haven't been a problem and I think the tummy ache was just due my old guts getting acclimated to a new medication.
All that said, I am in a similar boat financially, my insurance wasn't paying for the Vyvanse so I ended up using my entire HSA contribution every month, and the Adderall is $20.