I am thinking about purchasing auto/manual life vest, what are yalls experience? Brands? Pros or Cons?

I've been thinking about getting one. Looks like Onyx is a good one. I think the major benefit is you can keep it on and fish without noticing it is there.

Academy had them on sale reduced from $89 to $59. I picked one up for my Wife.

Mustang HIT. Comfortable and doesn't inflate unless submerged. In cold weather when fishing alone I wear it all the time.

Got this one for Christmas and used it for the first time this weekend. Hardly even noticed it, and it's good peace of mind, especially when fishing solo or in the winter with heavy clothing on like Fishspanker said. It only takes once for something to go terribly wrong.

This is the same one I have used for the last year and really like it. Got lucky and caught them on sale for under a $100. Had me worried when I took 3 rollers over the bow running on Texoma a couple of weeks ago but didn't inflate...thank God. I had my bibs on with just a jacket and I was pretty soaked from the waste up and freezing. If it had inflated it would have added insult to injury! Can still be a little warm in the heat of summer but I mostly fish alone so I rarely take it off. Great product...if it inflates if I go in...hope to never find out!

I got one of these and sometimes i even think i forgot to wear it, but no its there thats how comfortable they are

Love the auto inflate. I forget I have it on sometimes.

I've had a Onyx from Academy for about 3 years. Very comfortable but to tell you the truth.. I have no experience of it inflating... I also know the CO2 cartridge doesn't last forever. Makes me want to test it this summer but afraid it might ruin it. Anybody have any experience with them actually needing to inflate?

Agree.
Pros: Very comfortable. Inflation cylinder good for 5 years if not discharged. Inflates when submerged under water and not due to rain, water splash, or humidity. The HIT model also has a back-up manual inflation handle. I wear mine at all times on the water.
The con on the manual vest is that if you can't pull the chord for some reason it won't inflate (knocked out, heart attack, etc). Plus the accidental inflation from rain, etc.

Pros: Easy to wear all the time and forget it is on.
Cons: You'll never want to go back to a standard jacket, and they are not cheap.

I think it was around a year ago that we lost a fellow experienced fisherman at Roberts that was fishing solo. The best they could tell from the evidence was that he fell out and could not get back to the boat. That was enough of a reality check to make me wear a PFD 100% of the time from when I left the launch until I returned. Relatively speaking, it's cheap insurance to ensure you come back home.

I fish alone quite a bit and this is exactly why I want one.

I do as well. You won't be disappointed. I've been using a Mustang MIT. Nothing wrong with that one. Only downside is that it does not have a D-ring for the kill switch. I found a deal on an Onyx Carbon Deluxe and am awaitng it's arrival. My passenger (when I have one) will get to use the Mustang once the Onyx arrives. Here is the best deal I found on the Onyx:
http://www.ebay.com/itm/251762904035?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

It was a slow ship, so I am guessing this seller is drop shipping from somewhere. I'll see once it arrives.

One note of caution on the auto inflates. I did read where there were some instances of ones left in rod lockers inflating. While all the details weren't available, I'm guessing there had to be a fair amount of moisture present for that to happen. So, if you take a good soaking while out, don't throw one in the rod locker for storage until things dry out.

I have had one of the mustang HIT vests inflate while the boat was in storage for the winter.
You might want to check out the cost of the rearming kits. If you have to replace one they are a bit
pricey. Other than that they are really comfortable. I wear the jacket style in cold or rough water
conditions, and the mustang in warm weather/water conditions.

Had friend drown duck hunting. Too many clothes on, I haven't fished w/o one since. Mine has 3 options (auto,pull and a tube to blow into.)
carry 2 extra co2's in my bag.
game wardens wear them. Had one tell me thanks for wearing it.