Re:8085 versus 6502 (Score 1)

6502 would get similar performance to a Z80 running 4x as fast.

Theoretically, practically it was 'only' 2x - 3x faster and depending on task even slower (the lack of registers hurt)

Many instructions were one cycle

Not a single 6502 instruction was one cycle, shortest ones were 2 cycles long (NOP, INX/Y, TAX/Y, LDA/X/Y with immediate operand ..etc) as soon as you needed to accessed memory it was 3+ cycles (zero page access was faster while normal memory access took 4 and more - like using indexed addressing modes crossing page boundary)