and I have no idea how there different and what's better,

there's the memory man deluxe with the delay and extra modulation as chorus.
and there's the memory man with chorus and the echo,
and the small clone and the polychorus.

what's the damn difference and why should or shouldn't I just buy a small clone and a delay pedal without any extra crap?
Wise Man Says: The guitar is obviously female, she's got hips, breasts... and a hole.
UG's Flamenco Club
From my experience, buying the individual effects and then combining them seems to work better for me. Others that have experience with the combo pedals like that may know more, but I have a small clone that I combine with a DD-3 and thats a cool sound.
2003 Gibson Les Paul Custom Shop (Limited Edition guitar #71 out of 250)
Marshall JCM2000 TSL-100
Marshall 1960 slant cab
Boss pedals
Crybaby wah

The Deluxe Memory Man, even without the chorus and vibrato, is a heavenly echo/delay pedal.
These go to eleven...
They're all great.
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.