I use one for my daily drivers and 60s cars. I got for $20 and it works quite well.
You don't always need to fiddle with the weights to get the bubble perfectly centered. For instance, if the tire is going on the rear of the vehicle, I just set it on the balancer, and if it doesn't flop to one side and is more or less in the center, I call it good and move on. You can't feel a whole lot of imbalance in most vehicles unless it is coming from the steer tires up through the column. I think for the price of the balancer, versus the cost of a couple wheel balances at a tire shop, they are worth it and in short time you will be able to consider that tool has "paid for itself"