I would go for the Katana, Its not a ” nasty, flimsy little machine" its very strong, its also got a wobbly prop, cruses at 110kts and very nice to fly. The Pa 28’s aren’t bad but the 172’s like driving a bus with flat tyres. Have a go see if you enjoy it!!. I’ve got loads of hours in katana’s and they are very capable little aeroplanes. BTW a local flying school uses them and people tend to go solo quicker in them than anything else.