OK, so overall, this thing is fine. Nice and sturdy and flat, which is cool. A couple significant issues to note:

Several places list the depth at 13", including the box (yellow circle). THAT IS INCORRECT. It is actually 10" deep (maybe 10 1/8" to be more precise.) The width is adjustable, although the measurements provided are not exact. Width goes from about 10 1/8" to about 16 3/8".

The width adjustment arms are too far forward to be of practical use for my laptop (14" MacBook Pro) so I moved them to one of the ventilation slots (red circle). It actually worked really well, although the arms aren't inset like they would be in their intended slot.

The little tabs that screw on the front edge (green circle) are kinda useless. They provide a small edge that might help stop a laptop from sliding off, but the same thing could be achieved with a rolled lip like the back edge. The only advantage to having them removable would be if your intended laptop/mixer/etc was bigger than the tray. Plus, with those in place, the tray becomes too big to slide back into the box for transport.

So, long story short, it's fine, but there's a lot of room for improvement. If it were me, I'd put those adjustable arms on all four sides, closer to the middle of each side. I'll definitely be keeping an eye out for the MSA5001.

This only cost $?! Sturdy. Screwed it right on to an old school mic stand pushed almost all the way down. Set the laptop on and was ready to go in just a few minutes.

I use it on stage for lyric / chord confidence.

Sturdy. Simple. Inexpensive but not cheap.

I have an ASUS laptop which the base is 15wx10d. It fits it perfectly and is so solid. I have it mounted on an old school straight mic stand. Laptop stays in place with no signs of coming off tray. The tray is well worth the money and I thought it might be a little flimsy....I was wrong. Easily adjustable so you can mount laptops, small mixers, recorders, etc. And it comes supplied with the all the knobs and slides needed to secure your piece of equipment nice and solid. And it puts it nice and close without reaching or straining your eyes. Will use it to see my digital mixer app. better Pick yourself up one....its great!

Using this for a Mackie Mix 8 to sit on top of after a music stand dumped my Mix 8. It's stable, sturdy, and works just fine. No issues, no complaints

I've owned this for some time now and use it for a variety of reasons, laptop, 6 channel mixer, and sometimes just junk. It's surely a very handy item for the price. Try one!

I figured this would be easy and affordable, but feel sort of cheap. Honestly, I don't feel that way at all. It's simple and solid, and given that I have a ton of extra mic stands lying around (as do a lot of venues), setting this up as an attachment is kind of brilliant. Smaller profile and easier setup/teardown than my friend's Roland laptop stand that cost almost ten times as much, and my MacBook stays right where I need it.

It also holds my ROLI Seaboard Block perfectly. The side and front tabs are at the perfect height to keep it from sliding around (an issue on most surfaces), but without getting in the way of the playing surface. Plenty of space behind it to prop up an iPad or a small interface, too. I wish the Seaboard AND my MacBook would fit on it, but now I'm just being greedy...

Better quality than I expected, On-Stage comes through again. They use to not be my 1st choice but over the last few years everything from them I have purchased has been top-grade for the price. As was the MSA5000. I matched it with a small tripod stand minus its boom that has an 18" (inch) lowest setting,goes up to 30-something inches, and it has been perfect for placing studio devices at my fingertips...laptops/tablets, desk top sized recording interfaces, for dialing in floor pedals and not bending over a gazzillion times while tweaking knobs to perfection,etc., even a FaderPort. I can move it anywhere I need to, holds my stuff with stability, and is made well. All good for what I use it for, plan on purchasing another to use in a live setting asap. Sweetwater delivered in 48 hrs, free shipping and the best price on the net. Sweetwater makes my life easier,sure appreciate their whole crew, all pros.

I bought this for an HP laptop that measures 16 3/8" across. Based on the vendor description of 16.5" maximum width, I thought this would be fine. But the actual maximum width is 16.34", not 16.5". On-Stage apparently forgot that the arms have a thin layer of rubber padding, and this make the total width a little narrower. I will need to grind out the edges of the slots for a little more clearance.

If your laptop is a little smaller you'll be fine, and the basic unit is good. But I can't take it to the gig tonight.

Had made a purchase, then found the mixer stand I was looking for after the fact. Called in, and within 3 minutes,the first order was canceled, and new order was placed. Love Sweetwater!!!

Got this little guy along with a tripod mic stand to have easy access to my Ableton Push on stage. I don't use the front tabs, but the side wings really lock the push on there. It's taken a few bumps, and the push doesn't come out. The whole stand would have to fall over for that to happen.