YES. I forgot to mention the chair.
We are professionals. As such we should not expect or even allow ourselves to be leaning forward while sitting on a client's 18" high couch, making our backs and necks ache because we don't prepare an actual work environment for ourselves.

Over the years, one of the lessons I have tried to teach beginners is that if it is possible, they should move the thing they're working on to the position most comfortable for them to work on it. Sometimes that's impossible. But if you've already tired yourself out straining to do something you could lay on a table, then you've shortened your possible work day and irritated yourself for no good reason.

I now buy Togglers occasionally by the hundreds (and separately purchase GOOD bolts for them by the hundreds), instead of much more often hoping that Home Depot has the right pack of twenty with the soft bolts that come with them. Similarly, I use that table to extend my work day. To those who might say this is lazy, I say there's nothing professional about your body being wrecked at the end of a day because you haven't thought out your working conditions.

This idea was proven valid a couple of weeks ago when I was paid to be on site for a network job, when all I did was bring my table and chair and a 19" monitor that I carry with me. Someone else did the work, but after an hour they HAD to have the table and chair!

[Link: walmart.com]

The table shown on that web page and described as "LifeTime 4' Fold-In-Half Adjustable Table" is about the same size, can be set to different heights, and is a tiny bit cheaper. There's a similar model by Cosco (not Costco) on that web page, too, but I prefer the white table to the dark table.

Once you've used a table with adjustable height, you'll find it more helpful than you thought it would be. To find those, look carefully at the table legs. If they change diameter on the way to the floor, they're adjustable.

Whatever you do, look at one of these in person before buying it.

The first time I used this table, I set up a jig on it for cutting 12" or so holes in the centers of 60 ceiling tiles for background music speakers. Every time I ran the rotozip around the jig I knew I was saving time, and because the table brought the work up a couple of feet, I was saving my back as well.