20 mil? What are you TALKING about. Meta 1-2 guns and other fittings are nearly free. A new character would have a hard time with t2 fittings. Name a frigate and I'll give you an effective 600k isk or less loadout for it.
Aside from that, the effectiveness difference between an officer fit frigate and a rat dropping fitted one would take scientific instruments to measure outside of artificial tournament settings or fitting tool readouts. Both would explode in fractions of a second vs a gang, and both would NPC at roughly the same unsatisfyingly slow rate.
Now, if you're talking t2 frigates that's a whole different ball of ham. I find AFs not as effective as cruisers for infinitely more ISK, but that's just me. A battlecruiser is far more cost/performance effective. I feel the same way about HACs -- BCs and BS are nearly as effective or more effective for a fraction of the cost. Most players agree, and fly cruisers and BCs for informal smallish scale PvP.