For beginners, the K5 and K6 are good choices due to their excellent value and playability. However, since this is your first radio, you'll need it for applying for a license and obtaining a callsign. Therefore, it's essential to choose a model that can be inspected locally. Since inspection standards vary from place to place, it's best to contact the local "No-Wei" (local regulatory authority) department responsible for inspections in advance to confirm whether your desired model can pass inspection or to seek assistance from a local ham radio operator.