[Festus2]

Some TT have electric jacks all round while others have manual ones. I think it is a matter of personal preference and how many of the labor-reducing options you want. Many members who have manual jacks use a cordless drill with a 3/4 in adapter on the end so there is really no physical effort needed to raise or lower the jacks. The time taken to do this task is also reduced.
Some members may not be physically able to manually operate the jacks and having electric jacks is a requirement for them.

I think you have to weigh what you need vs what you want as I don't think that there is too much difference between the two. Both have pros and cons.

The downside of electrical components is that they are more susceptible to failure than the manual ones. There isn't much that can go wrong with manual jacks. The other negative is the additional cost - if they are an option item.