Some good advice from above replies. Just a few words on the katana. Did some hours early on in my training 17 years ago. Loved the aircraft and the great visibility. Only transferred to a PA28 due to lack of availability on the katana. Advantage vs PA28 or C152 is the c/s or wobbly prop. Hours spent training on this type will qualify you for other complex aircraft in the future should you wish to fly one. The katana is a slippery aircraft compared to most other trainers, and the skill needed to control speed on approach is IMO a useful extra tool to have. If you can nail the approach in a katana, you will find a PA28 easy.