I think there is a market for the ace, but not a market for 6 different models (325, 500, 570, 900sp, 900xc, rs1).
I don't get the rs1, it's bigger in all dimensions than an rzr 900 trail or even a 900s.
I agree polaris just did a terrible job promoting the ace. Until a few months ago I had barely heard about it, everything I knew could be summed up as "a 4 wheeler with a roll cage", which it seems to be how polaris marketed it, but was a turnoff for me as an atv rider, and is definitely not the reason we bought one.
Basically, I used to be all about atv's. My daughter loved riding with me, but at 12 was getting a bit big to be riding on the back of my 1up ATV, so I started looking at 2 seat ATV's, and then needed the make the decision between a 2up atv and a 50" rzr ...
In the end I decided on a 50" rzr 900 trail, and we loved it. That and my wife's atv fit great on our trailer.
Then one day my wife drove my rzr, and was hooked. But, there was no possibility of fitting a second rzr on our trailer, and due to how we need to park it next to our house, we have a tight 90° turn that necessitates using a trailer dolly, a double axle trailer was out of the question, and any single axle we could find didn't have the weight capacity for two rzr's, even my 900 and a 570 would be about 25% over weight...
Then one day mulling it over, the ace enterd my mind, not as a "safer atv", but as a "smaller sxs".... Basically, we were the perfect candidate for an ace, we wanted a "sxs", but we only needed one more seat, and we needed something smaller than the smallest sxs.... Litteraly only an ace fit our parameters.
Next came the real problem. Finding one. The 325 was definitely out, as it would have the same problem as our atv keeping up with my 900. The 500 that replaced it seemed no better with the same 32hp. The 570 seemed perfect, but finding one for sale nearby was a challenge. We expanded our research area to 500 miles, and still nothing a few 500s came up but were gone before we got the chance to call...... Then we discovered the 900sp via a classified ad....
The price seemed a little high, but it came with a ridiculous number of extras. Winch, an aluminum roof, lower doors, front and rear bumpers, a radio, rock rails, a nice skid plate, street legal kit... We paid $8450 for it, which I feel was an ok deal considering corona pricing...
Anyway, the point of my post is, aces are really only tough to sell because no one is really looking for them. For somebody looking for one, there is simply no competition, and now that you can't go new, they should sell even better.
Imo the only reason one isn't selling is not because it's priced too high, but that simply no one is looking, because they don't know about them, so don't lower your price, you just need to wait till a buyer comes along. We litteraly bought the first one we called on that wasn't already sold, and looking now there are simply none for sale nearby, so we are glad we did...