It’s really hard to tell you if you are going to have good results with one version or the other. Individual results are going to vary depending on how you use the HUB, how your movies are encoded, what and how you connect external drives, etc…
No one person can tell you which version is going to be best for your needs. However, the only real improvements between 2.07 and 2.04 is that with 2.07 you can attach larger than 2TB drives, you can use locally stored backdrops, and you have more services to chose from.
As I said though, the bes thing for you to do is to just try a version. Start with 2.07, then if you don’t like it or you find it has bugs that you can’t live with, then just rollback the firmware to 2.04. This is going to be the only way you’ll know which version you like best, because asking others which is best for you is sort of like asking a bunch of people if you would like sushi. Some people will tell you that its great and that you’ll love it and others will tell you it’s gross and that you’ll hate it, but the only way you’ll know for sure is to try it. The only thing that the majority of can agree on is that we don’t want cooked Nutria (that being version 2.08).
But in case anyone does like version 2.08, HERE’S you a recipe.