That is a difficult question to answer because much of it depends on you. If you hate small monitors, then an ackie is not going to be a good one. You will get bored or disappointed with it. If you love large monitors but do not have the space, then a water is not a good one. You may love it a lot, but not be able to keep it correctly. There are so many factors to consider.
There are some trends though. You already stated a water monitor gets too big. Niles are usually pretty nasty tempered animals. They also get fairly large. This is probably not a good monitor for you. They need a lot of space and very rarely calm down.
Ackies are small and interesting. I would keep looking around for an ackie if you think that would be something you would like.
Savannahs. Most people rag on savannahs because they are all WC. They are a very common monitor (I have seen them in Canada) which leads lots of ill-prepared people to impulse buy them. These monitors then live very short lives. This gets frustrating for more dedicated monitor people and when asked about savannah monitors, these monitor keepers tend to overstate the problems of savannah monitors in an attempt to change the minds of impulse buyers.
In my opinion, savannah monitors can make very good monitors to keep. They tend to be more laid back compared to many others available. They average around 3 feet, not too big and not too small. A savannah can be an aggressive animal and a bite will hurt a lot when fully grown. There is no guarantee it will be calm and tolerate you handling it. They do eat a lot so you are going to want to have a good supply of food available, buying rats/mice at the local pet store will get very expensive if you take care of a savannah monitor correctly.
So, if you like the way savannah monitors look and you are prepared to properly house and feed a savannah monitor, then it might be a good monitor for you. Otherwise, keep looking for a better monitor for you.
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^x^ Bloodbat ^x^
