In addition probes should have a footprint small enough to enable you to scan the smaller structures with ease. It s very difficult for example to scan finger joint with a probe much longer than 26mm. Probes should be light, easy to manipulate, and not lead to discomfort for the operator over a long scanning session. Large adjustable monitors lead to a more relaxed working position and portability may be an issue for you if the scanner has to be moved between consulting rooms. Manufacturers often use different ways of specifying the frequency of their probes and this can give rise to some confusion.
Lets look at a specific example to clarify the position.
This means that the bandwidth of the probe is 6.0 MHz centred on 10.0MHz, so the probe operates between 7.0-13.0 MHz. In the near field the scanner electronically filters out the low frequencies giving higher resolution and in the far field the electronics lets the lower frequencies pass through giving better penetration. Whatever you do make sure that when you arrange a demonstration all the probes that you need to evaluate are available for your use. Promises of probe developments that may lie just around the corner are very easy to make and usually much harder to keep.