Yeah, basically, the choice depend of if you have (lots of) retail games you want to play with, because even if Classic Mode is available on 4.x, the saves won't be recognized if your retail game saves use 7.x+ encryption.
And has Classic mode in 9.2 support 7.x+ encryption, you can still play online to retail games which require updates as you can access eshop on emunand.
Not to mention blue card can also be reactivated with a .cia file installed on sysnand and also the fact that I don't think playing DS games on 9.2 sysnand break the exploit as it don't use the Nintendo DS profile exploit (on 4.x, you have to reinstall the exploit every time, even though it only take a few seconds and you can always reinstall it easily as you can leave the exploit with your other ds roms, if you use the blue card).
For someone who don't care about retail games though, 4.x is probably the best choice.
That's my main point to downgrade.. you don't need the browser... They have been hacked before, the website can go down forever you never know.. One day they can just catch ghost! and loook you have a POS flashcart that can't be used..
They are already several mirror websites for the exploit, so this risk is pretty low (maxconsoles have one, for example). Same for the Gateway website, they are several non-official mirror websites.
What version is more stable? I heard sth of that the exploit of 4.5 could self fix it, so that couldnt get into Gatewaymode anymore? Is it true?
Stability is more or less the same for both exploits. Both sometimes fail to load, it's quite rare for both but it can happen.
Downgrade. Having to use the browser exploit is a pain in the ass compared to the DS profile method, and you can use NTR CFW for screenshots. Plus you cannot generate xorpads on 9.x, and if you're going to use emunand like any good GW user, there's no actual reason to have your sysnand on >4.x. Lastly, the home menu takes much longer to load on 9.x.
And yes, you can always upgrade back, but why would you want to?
In fact, loading the 4.x exploit take more time than the 9.x exploit (which is balanced by the fact 9.x is a little slower to boot).
4.x (assuming the cursor is on "system settings") : Enter in the settings (one click), Other settings (one click), User profile (one click), DS profile (one click) so four clicks to launch the exploit.
9.x (assuming the cursor is on the browser icon and that you added a favorite for the link). Launch browser (one click), favorites (one click), gateway website (one click) so three clicks to launch the exploit.
So it's more or less the same for both exploits.