A Wide range of tunings is made depending on the needs.
Presumably You would be pleased to have Your new instruments tuned at the same pitch as the other instruments you might have.
Although the difference is almost unnoticeable, the two most used common tunings are:
The standard pitch 440 Hz (mostly German instruments, electronic instruments default setting)
Orchestra pitch 442 Hz (often Italian instruments some German cassotto instruments, accordions in Finland...)
The instruments can be tuned also 441hz to have almost satisfying consonance with both described tunings.
The amount of the „violin“ tremolo is also a matter of taste. You can order all tremolos starting from classical dry tuning to wide French tuning.
Extra wide bright sound is gained with triple-tremolo musette sound. One option is to choose the model with an extra reed block added. (The extra reeds add additional 2.5 cm to the width, 800g to the weight and some hundreds Euros to the price of the instrument.)
The second option is to have the piccolo reed block replaced by an extra middle reed block. (The price, width and the weight remain the same but you have to give up all the register combinations with piccolo.)
Click the links above to compare the different „violin“ tremolo tunings (A440)
+0Hz c +2,5hz c +4Hz
+1hz +3Hz +4Hz c
Cassotto is essential e.g. in swing music: