shall I switch from w.machine to meg or tig

[great adventure]

dear guys,

so far I am using italian wilding machine a/c and dc
it weld aluminium and steel.

do you recommend me to switch from welding machine to
tig or mig, if the answer yes which one shall i buy the tig or mig
as still I dont know the difference between them

thank you

 

[1320stang]

What do you primarily weld now and what do you desire to primarily weld?

I'm asking both for what materials and what thickness.