When it comes to choosing a motorcycle, it's important to consider factors such as your height, riding preferences, and overall comfort. Both the Suzuki Gixxer and Yamaha FZ25 are popular choices in the 250cc segment, but your height of 5'6" may play a role in determining the best fit for you.
The Suzuki Gixxer has a seat height of around 795mm (31.3 inches), while the Yamaha FZ25 has a slightly higher seat height of around 795mm to 800mm (31.3 to 31.5 inches). Given your height, both motorcycles should be reasonably comfortable for you to handle.
Factors such as the seat width, handlebar positioning, and footpeg placement can also affect how comfortable you feel while riding.
Additionally, consider taking a test ride on both motorcycles if possible. This will give you a better understanding of how each bike performs, handles, and whether it suits your riding style and preferences.
Ultimately, the decision between the Suzuki Gixxer and Yamaha FZ25 should be based on your personal preference and comfort after considering these factors.