snap on modis as data logger on 1g?

hey im hoping kevin or somebody will know what im talking about. the garage i work at has a modis and all the adapters to hook it up to the diagnostic port on a 1g. would this work as a datalogger it can show all the fuel trims and o2 sensor monitors and everything. what all does a normal datalog have in it. also is a datalogger something ill need every day or just once in awhile when i do a new mod and need to adjust stuff?
thanxs