i have been reading quite a good deal of information on the obd1s and 2s on this site, but most threads did not provide a complete answer, so once again what are the advantages of having
a) obd1 over an obd2
b) chipped obd2
c) chipped obd1(?)
....for a 2000GSR.

and is it true its as simple as plug an play? and what are the possibilities for deterioratin in drving quality?