Agree.....
Right now those emulators are getting really good, but of all the feature that are arguably useful, I think TZX or TAP support (more tzx) is really essential.
Most of the games are stored in TZX format, and going around making Z80 or SNA files out of them is a pain, and can result in bad snapshots with hardware emulation issues.
Think about it, if an emulator supports TZX then even an humble 48K Speccy can run the majority of the software, even the big multi loading games.
Therefore I always put TZX support in front of 128K emulation first, as it directly affects the number of games that we can run.
Now having TZX and 128K that would be really an accomplishment for an NDS emulator !
I agree though that russian games for the tr-dos are fantastic
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