I'm trying to decide which canopy to buy and I'm not sure which is the best buy.
Is an aluminum frame good enough or is steel the only way to go?

Are the lower stabilizing bars that run along the ground a must have? They look like they would make the frame a lot more rigid. Would you trip over the bar much when walking through the rear door?

Do all of the heavy duty models have the sides zipper to the roof?

Lightdome looks easiest to set up... is it?

Any help would be appreciated

I've had the lite dome for about 9 years & have replaced the legs several times as aluminum bends.
The stabilizer bars sound like an excellent addition but I'm still undecided as I store behind & constantly need to pull stock, I'm afraid of tripping on it.
On the plus side, although the top is difficult to put on by yourself & I always have to ask for help, it's quite easy for 2 people.
Also, it's much lighter than steel & the dome shape works well in the wind.

I think the Showoff is the best buy; it's strong aluminum, one person can set it up, art buyers like the roominess and high ceiling, part replacement is available, can customize ( Idid), and it is fire retardant. And amazingly it is made in Clearwater USA.
My experience had been very good with the showoff, it has withstood weather conditions when other canopies did not fare as well.
I also have their display panels and I love the versatility and self sealing hook holes. I have recommended the showoff to friends.