Plc Conversions

I have 4 different PLC's I would like to crossover to a Siemens S7 model. I know the I/O is important, but I'm just looking for a generic equivilent. The 4 models are,
1)Allen Bradley Logix 5555
2)Allen Bradley PLC 5 20E
3)Modicon 486 controller /CPU 424
4)Klockner Mueller CPU A5 EBE 221.1
Any help would be appreciated and I'm just looking at a ballpark crossover. THANKS!

I think the high end of the 300 series is probobly compatible on average. Take a look at the 318-2 DP processor.