The MMF5 is good, but may require the old "Rega Nudge" for assistance in getting the platter up to speed quickly on power up - but it's not really a big deal - I've lived with it for over 30 years :-)
You can then afford a pretty nice phono stage.
However, I would prefer the drive band going around the outside of the platter, like the MMF 7 offers. It gets the platter up to speed faster and it may offer a more stable rotational speed.
The other MMF7 features I really like are
- non resonant acrylic platter
- motor sits on its own resonance damping puck
- counterweight’s center of gravity level with stylus tip
But then selecting the MMF5 would allow more to be spent on the phono stage
Tough choice, but I'd go with the MMF7. There are still some very adept phono stages out there for around $500
Regards