Between the A&H (16:2, I believe would be correct) and the Mackie VLZ, I'd take the A&H without question. The A&H is simply a better sounding board. 2 sweepable mids in the EQ section, and much better sounding EQ all the way around. Better preamps too, but by a fairly slim margin. If it's the 16:2 DX (Mixwizard 2 or 3) it has some effects too. Nothing grand, but I use them.

I'd also say the A&H is more robust than the Mackie - more metal in the case, nuts on every knob, and longer throw faders to boot.

I don't have any experience with Onyx.

The A&H's I own are a pair of GL2 rackmount units that have served me very well. The MixWizards are not built as robustly, but they are a bit less expensive. I have seen NOS GL2s on the internet going for over $1K.I also use several Mackies (1604,1642, 1202s,etc). I haven't had any problems with those little VLZ buggers at all. I think that ANY gear that is treated roughly will give the owners problems down the road. How rough does that used Mackie look? That should tell you something. IMHO, the biggest difference between the A&L and the VLZ is ...HEADROOM! The A&H's will deliver a better, cleaner signal on peaks, and that IS a big deal doing live sound.
Now, for the speakers... the Yamahas are made in the States and use very good Eminence components throughout. I believe that the series you name uses cast-frame woofers, but I'm not 100% on that. They are a great value, and tough. My experiences with Mackie speakers, as co-owner of a speaker-rebuilding business, are not so good. Their cabs use RCF components, and the failure rates of that line are much higher. We have noticed that the adhesives RCF uses in their drivers don't really tolerate heat that well, and that leads to premature failure. They do sound good, but so do the Yammies. I have taken my Yamahas out on "small" gigs so many times, and they all have "weathered the storm" so very well. Highly recommended.

Here are some facts (and opinions) to help you make your decision:

Mackie products have gone down in quality since they are now being built in China (i.e. they are not as reliable out of the box). Tabulation of failure rates out of the box compared to 1 year ago support this.

Each potentiometer on the A&H is knutted down to the board so they don't wiggle *at all*. This creates less stress on the circuit board, and is better for long term useage. Mackie does not do this so next time you go to see a 1604 (either VLZ or Onyx) in person, wiggle the knobs and you'll see what I mean. 1604's are infamous for their ribbon cables going bad.

Mackie has the optional firwire board whereas the A&H has sys-link; the ability to expand your channel count by chaining another sys-link equiped A&H mixer to it. Therefore, the A&H is scalable and the Mackie is multi-purpose.

A&H has 100MM faders vs Mackie's 60MM. Mackie has no f/x built in whereas the A&H does.

A&H mixers have individually switchable +48V on every channel whereas Mackie is globally on or off.

Mackie has 4 bus vs A&H's 2-bus.

My opinion is that the sound of the A&H will spank the Mackie. I've heard it for myself and heard this same sentiment repeated by customers time and time again.

As for the speakers:

Yamaha uses 2" HF drivers which project better at lower distortion specs. Mackie uses 1.75".

The Yamaha's program power rating is 500W @ 8ohms vs Mackie which is 700W @ 8ohms. Therefore, being that there is only 1 db difference in their sensitivities, you will need a more powerful amp for the Mackie speakers to accomplish the same db/output. That means more $ for the amp which drives the Mackie vs less $ for the one for the Yamahas.

Yamaha's a 7 lbs lighter, and sell for almost half the price of the Mackie.

Hard to justify the Mackie with facts like this.

I hope this helps.

It is not fair to blame Mackie failure rates on the Chinese. It was an issue long before the move. SR series small and large were all crap before the move. I was selling Mackie when it first hit the streets. When you are building for a low ball price point, there has to be some sacrificial engineering and manufacturing.

The new Onyx consoles do not feel sturdy to me. The original issue 1604s feel much more solid. But, the average buyer of these is going to treat them well. Any super abusive pro environments wouldn't allow for either of these to be a cornerstone in a system, so it can be a moot point.

You should let your ears be your guide. I am not an AH or Mackie fan. Both have entry level product issues in their history. I will say that AH tech support is very good. They respond quickly so that problems may be handled in the field as much as possible.