Sencore CR-13

I just bought a sencore cr-13 crt tester that needs to be recaped for $20 and i neede to know 2 things.
1) Is this even a half good tester(uses the same set-up and tube test data as the cr-70) or did i just waste $20.
2) As this is the first time i have ever had to repair any test equiptment i need to know if it is important to use new caps. of the exact same value as the old ones or is there the same small amount of room for error as you have i radios.

Nick