Comparing a portable aluminum track ramp vs flat portable suitcase ramp, for a caregiver to push their elder in a wheelchair. Experiences?

We like our Prairie View Industries ramp very much. They have a very solid feel to them and have a level indicator on the side to help you see if the angle is in the safe zone.

We have the 6 foot fold-able version that is mainly used for a space with one step up. A wheelchair user can go up and down it alone if they can push with their feet (going up backwards).

Occasionally, we move it to a spot with two steps, where the wheelchair user needs assistance to safely go up or down. I wouldn't want to use it for a place with three steps for anything but non fragile objects.

Here is their calculator for what ramp length is needed.
https://www.pviramps.com/products/calculator

So it looks like they have a 12 foot ramp that might work for an accompanied user to go up 22 inches.
https://www.pviramps.com/products/product-details/id/206

Since it is almost 100 pounds, I'm not sure if I'd call it portable. Nor is it inexpensive, but if you want something that a novice can "install" so you don't have to work with strangers doing construction, it could work.

I have to admit that I had an s shaped wooden ramp built for my home which gave me the ability to take mom out often (several times a week) for walks, if I had to muscle my way with anything as makeshift and potentially dangerous as you propose I don't think we ever would have left the house. I would only attempt this as a way to get somebody out the door if absolutely necessary a few times a year, and only then with the two person assist you mention. As you have discovered going up is easier than coming down so long as you have the physical strength, going down backwards is the only possible way to keep the chair from running away on you as well as avoiding possibly tipping the person right out of the front of the chair.

clarification; In order to get a bit of a sample of how these tracks might work, I rented a pair of 11 inch wide x 80 in (6 ft 8 in) loading ramps at home depot and although each ramp did not have a side rail to keep the wheels within the 11 inch track, with careful attention to walk up while keeping the wheels aligned on the tracks, it did give me the benefit of getting a feel of what the pushing upward feels like with bags of sand and dog food as my passenger. I found that going up was easy because i was able to have the benefit of placing my feet on the steps between the tracks while walking upwards. (This was just a test so dont use cargo loading ramps as wheelchair ramps because the wheels will roll off.)
Going downward was NOT possible facing forward as a passenger would fall out at this angle. I did have success going backwards at this angle while stepping down the 3 stairs also backwards but it requires strength a lot of strength and focus and i consider it impractical and best with two people assisting the wheelchair down.

What i like to know is,
What is the experience like using a flat ramp and the caregiver pushing the passenger on a similar rise size or the next step ramp which is 8 ft? (track or flat ramp)
I only used a ramp which was 6 ft 8 inches long and they were separate tracks with the space to walk up in the middle. Would getting an 8 ft ramp as a pair of tracks or solid ramp be so much better?
I have read that in residential settings, the ratio is every 2 inches to 1 foot of ramp. So in my case, that would be an 11 ft ramp.

The recommended ratio for ramps is 1' length for every 1' of height, so either choice is going to be incredibly steep and difficult (possibly even dangerous) to use. It seems to me the track ramps would be pretty much impossible because because the person pushing the chair has no place to stand, even if the tracks are able to be pushed close together straddling them would be awkward at best.