Help me get into Shin megami tensei/persona

[Dioxinis]

koreanmatt said:

Start with Persona 3 IMO. I found a copy for $3.99 at Gamestop near me last time I went there. Or, get Persona 4 then get Persona 3 for PSP later.  

is persona 3 fes the full game with bonus content or is it STRICTLY an expansion? i geuss if i enjoy that i'll move on the persona 4 then perhaps i'll try persona on the psp

 

after that what about devil summoner or digital devil saga? (assuming i enjoy those other 3 games)

 

thanks for the input thus far