The Snapper Hi-Vac is the best bagging mower on the planet in my opinion. It does well at mulching and side discharge too. I have both mowers. The Lawn-Boy is a good one too but it can't match the Snapper's bagging talent.

If you are willing to go beyond those two manufacturers also take a look at the Toro Super Bagger.

I have a 22271 and it has been great. I would have to get the 22270 if I had that same choice. This deck bags so well that when Toro uses it on a residential mower they call it the 'Super Bagger'. Part of the great bagging is the rear discharge set-up that has a huge, short chute blowing directly into the bag off the blade ends. The bag is big, too, and the system is the easiest there is to dump the bag or change back to mulching. With the mulch plug in, you can open the side discharge port, hang the chute on it and be side-discharging in 10 seconds.
Then you have the real goodies; thick cast deck, Honda commercial OHV 190cc engine and steel modular wheels with replaceable tires and sealed bearings.
Toro now badges this mower as a Toro commercial, so there's no concern over parts availability. For that matter, the only real reason to grab the 22270 instead of the Toro might be the price, because the Toro lists higher than the LB did and the LB should be on special right now because its a close-out.
I don't think there can be any comparison between this commercial mower and the homeowner Snapper. How good do you need bagging to be? No mower is perfect and they all will miss a leaf or two here and there, but I've never known mine to leave any grass clippings visible when bagging.

Thanks. I'm getting pretty consistent responses on the Snapper as a bagger. I now do all of my yard with a 48" deck set up for mulching and a weed whacker. I'm looking around for a push to bag on occasion and to better manicure a small front yard. I have sections that are pretty well infected with poa that I would rather bag. I've never owned a self-propelled mower so thought this might be a good opportunity. Only tractors and cheap push models for trimming. I thought I had found a good companion to the tractor in the Snapper, and it still is, but the Lawn Boy green with orange wheels is awfully tempting.

I'm pretty sure blade selection will have an effect on the performance. Saxman1, what blade are you running? Atomic? Your comment on the change over to mulching or discharge is one I'll have to think on. I suspect the Snapper with the high lift wings won't mulch as good if I wanted to change "on the fly." I'll have to download the manuals and make sure I know the procedure for each. I wonder what a "cut off" would reveal if each was spinning a gator blade.

The Snapper converts from bagging to mulching in 5 seconds with a mulch plug. It mulches about as good as any Lawn-Boy. I should know I have about 25 of them and 4 Toros. Side discharging on the Snapper takes a couple minutes.

'I've never owned a self-propelled mower so thought this might be a good opportunity'

LB22270 is not self-propelled.

'Saxman1, what blade are you running?'

Factory blade on the 22270-22271 is just like the 'Atomic' but without the 'chopper cuts' on the back. I have both kinds of blades (Atomic and plain) and run them both interchangably on LB10684 and LB22271 - have not been able to tell any difference.

' if each was spinning a gator blade.'

I would view it as counter-productive, if not idiotic, to pay a ton for a premium mower, then take out the OEM blade and put in a generic aftermarket product.

'I suspect the Snapper with the high lift wings won't mulch as good if I wanted to change "on the fly."'

Nobody changes blades to mulch unless they will be mulching-only with that mower. The factory blades function fine in all modes of operation. The 'wings' on the blade are there for bagging, but they also keep the clippings circulating in the housing to be re-cut when the discharge port is closed.

For your application I would not even bother with a premium or commercial mower. Check out the 20" LB 10641 sold only at Home Depot for about $300 or less depending on exact model.

Here is a link that might be useful: Lawn-Boy 20

"The Snapper converts from bagging to mulching in 5 seconds with a mulch plug." Thanks rdaystrom, I saw how that worked in the manual.

"The factory blades function fine in all modes of operation."

Thanks. No recent experience with these type mowers so wasn't sure. Usually, multi-purpose isn't as good as a single purpose.

Would anyone know where I could buy a new Lawn Boy 22270 commercial mower?

Thank hyou

Wow. They only made a very few in 2007 and I doubt there are any new, old-stock ones still hanging around. However, Toro still makes the same thing painted red and white instead of green and orange. Its the 22156.

Here is a link that might be useful: Toro 22156