Based on your needs, I would think either should do the trick.
Personally, I would get a new Mini-14 in stainless and never look back. If you want to tacticool it up, you can, but it's a perfectly good rifle just off the rack.
Of course, they also make the Mini-30, which takes 7.62x39, and is like having a semi-auto 30-30 when you load soft-points (still very cheap). That's what I would get unless you needed the flat-shooting of the 223 for longer-range varmint stuff. How far away are you planning to take your varmint shots?