I was looking at the summit racing wheel tubs, and they are priced nicely for around $75 a pair. The issue I see is they are only 24 gauge sheet metal. Other places are $50 more a pair, but are 20 gauge instead. Is it worth the extra $50 for that little amount of thickness? This is on a street car that is getting mini tubbed with street tires.

24 gauge is really thin steel. I'd avoid them.

You can jab a screwdriver through 24ga without much of a swing.

Is 20ga much stronger? Or should I look for thicker?

20 is probably OK, especially if the have some bead rolling in them (?). The stock sheetmetal is probably 18-19 ga so 20 is not far off.

Personally when I have done tubs in a street car I treat them like a factory wheelhouse; I usually undercoat the outside and use carpet or Dynamat on the inside. It adds a lot of noise reduction and helps prevent dents and dings.

Thanks for the info.

I have found a set of 16 guage tubs for $129. here is a link:
http://store.gaugemagazine.com/32-round-universal-wheel-tub.aspx