I would say that is overkill. Once a year is standard if you know the signs of illness, twice a year is extra great. Any more than that and I would say you are actually doing more harm than good by exposing your pets to the illnesses in a vet clinic as well as the stress of the visit.
I am a paranoid bird owner, I literally have nightmares about my birds dying. I also know that I have an anxiety disorder that contributes to my paranoia. It might be wise for you to examine your reasons for needing to take your pets in so often. For me personally, learning everything I can about avian health, medicin, nutrition, etc, helps me know my birds are doing well.
Here are some things you can do to help you feel confident you are in the drivers seat of your birds health. Most of these I do myself.
Weigh each bird weekly and keep a record. Weight loss is often the first sign of illness and is easy to miss. I bought a gram scale at Walmart for around $20. Easy and about the most overlooked health precaution in my opinion.
Weekly examin the eyes, nares, and ears of each bird. Know what you are looking for. Check for visible signs of mites or skin irritation.
Keep a food journal for your bird, and keep a sharp eye on the poop. Learn what foods make the poop look different, so you will know if something actually looks off. For example I have a bird who pigs out on watermelon and then has watery droppings for several hours afterwards, totally normal. But if she starts having watery droppings in a day she has had only pellets... Sign of trouble.
Avian biotech has some great blood and swab tests that are quite affordable and provide a wide range of diagnostics. I test my flock for polyoma, pbfd, and psittacosis every 6 months.
Deworm your flock once a year if they live outside.
Find a vet that will let you bring droppings in for gram stains or fecal floats if they have your bird on file. That provides you access to the tests without subjecting your bird to the stress.
Be obsessed with the species specific nutritional needs of your bird. Know what nutrients they need during which times of the year, their natural diet, etc. go all out. Learn what they need to thrive and give it to them. Include things for their health that might seem extravagant like fresh organic produce, etc. focus on preventative health care. What I mean is, do the actual prevention by making sure they have access to the things to keep them healthiest, not just by taking them in often to catch problems early. Think about a human. If a human had two options for health, which would be best? Eating a healthy diet, getting enough sleep, good excercise, good hydration, low stress, etc, or simply doing whatever they want but going to the doctor often? Best to support the health rather than searching for health problems
