From my experience, emulators are released specifically for a certain title - I haven't come across any game yet that has the same emulator, at all, that is used in other titles. However, there are definitely what I consider "Magic Bullet" templates which work for a majority of titles and fix issues in older or newer templates - sometimes Sony puts out an updated template for the same game, which fixes issues in a prior version. These are the ones I recommend sticking with for best results;
Rogue Galaxy v2 (and its predecessor Rogue Galaxy v1 or "
Olympack" as it's labelled in Docs\revision.h) = definitely the most compatible and fastest. Less accurate though, so games can often show more issues or even not boot at all, stuck on a black screen after PS2 logo.
Star Ocean 3 = More accurate and slower than RG, less accurate and faster than Jak & Daxter v1/v2. This is a good middle ground, something
@stayhye and I have had happy results using.
Jak & Daxter v2 = The most accurate and, kinda almost, the slowest template yet. This is great for games that aren't system intensive but do show severe graphical/etc issues in earlier templates. Also great for loading games that refuse to load on earlier templates, like Rogue, which show black screens after the PS2 logo.
King of Fighters 98 Ultimate Match = Most recent template we have available to us, highly accurate and with the included fixes it's *great* for 2D/sprite-heavy titles. I've used this to fix several 2D fighting game collections, specifically anything from Capcom or SNK. I haven't had great success using it on 3D games though.
If we eventually do see a 5.55 kexploit released (which I'm starting to doubt, to be honest, too many scene devs have outright stated we shouldn't wait for one and how its only use would be piracy so they don't care) then I already know several awesome dudes who are currently sitting on a proverbial goldmine of unreleased PS2 Classics -- so that'll be a WICKED FUN day :biggrin: