While I am just now learning more details about electric violins, I would add to the above comments that you will find that many inexpensive models are quite heavy. This may be a nuisance or hindrance whether a beginner or established player.
As Micheal points out, string quality on economy instruments, electric or not, leaves a lot of room for improvement,
The economy model electronics as mentioned are less reliable and may have less than desireable sound qualities.
And again, electric or not, the “setup” and playability are often what sets a quality instrument apart and the labor involved can add to the price, but add a great deal of value at the same time.