No. Ester C is just buffered with calcium so it won't have an acid problem and you can take a lot more. They also add Citrus Bioflavonoid so it's a little better than Ascorbic acid. I paid $22.49 at a local health store for 240 500mg capsule.
Camu-Camu looks like it is made from a plant so it might be better a more natural source and more bio available.
If you want to take a lot of vitamin C Ester C is great. If you want a powerful anti oxidant OPC's are 20 to 40 times stronger than vitamin C.