I would definitely recommend a pivotal machine for help with balance. Linear machines are great but don't really stimulate the stabilizer muscles that so many people are weak in. Tri-planer and spiral machines are the best for helping with balance. If you don't need to go to the low hertz then a spiral or pivotal machine can be best. If using strictly for body building and toning and you don't need low hertz for lymphatic drainage, then triplaner is probably the best for most people for balance.
Notice: for people with balance problems, I would AVOID machines that give off high EMF unless you put a EMF blocking sticker on the outside of the motor or plate. Blocking EMF makes a huge difference in balance and you can google or go on Youtube to see what emf pendants do. But, the EMF that comes out of many machines, I would not recommend them to people who already have balance issues and getting jolted with more EMF makes the issue even worse. I am not making this up. Many people never heard of how EMF affects balance. I can show anyone proof of what they do. Just about every person in professional sports wears one. The ones that work costs wholesale usually under 15 dollars. Good ones can cost as much as 300 dollars wholesale that are infused longer.
If anyone news a machine that requires more power that creates a lot of EMF, I would not use it without an EMF blocking sticker. Ask me about availability of EMF blocking stickers - I have 24 carat gold stickers that I am able to offer at a discount. Please note that DC motors emit much lower levels of EMF. Depending on how much EMF your machine makes will depend on how many stickers to put on it. Usually about 6 is enough. If you don't want a machine with high EMF, and you are not sensitive to EMF, let me know. All of my DC motors are low to negligible EMF.