I don't know where you're seeing Fox Mustangs for $10k, but if you want one for $5k, let me know. They are for sale around here for $1,500 to $2,000 all day. I'd be happy to save you $5k while I make $3k. LOL
Argument is it costs $10k to buy and build a 10 second fox and $20k to buy and build a 10 second Mod car.
10 second foxes are also retreaded slow on the street since they are 100% drag cars that are running a 10.98 at 90 mph because they have a .0006 60/ft and .0004 reaction time.*
*exaggeration