An older 600 CBR is only so-so to learn to ride on. At 105hp (98 model) it definitely has enough power to hurt you/throw you/lose control if you make an error.... so you'll want to take it easy and progress very gradually.

Katanas aren't very well regarded by some riders. I think the problem is that EVERY other bike suzuki makes is better than a Katana (GS500, GSX-R, SV650, SV650s). They are heavy and about 86hp, though