You can usually catch a deal at Mirage (Negril One Stop has a good one now), but the published base rates are little on the higher side. Nadine quoted me over $120 for a third floor room in November of this year, if I booked directly with the hotel. You can get Pisces or Little Capricorn at Catcha for less than that. During the winter the rates go up to $200.
I agree, that Tensing will be priced higher that Mirage in almost all cases - but in some scenarios, you can get a room Catcha for about the same rate. It all depends on what amenities you are willing to trade off on.
When I said that Mirage tended to be priced on the higher end, I was comparing it other cliffside hotel like BCC and HSH where you can get a nice seaview room for $75 during the slow season. You can get a room at Negril Escape even cheaper, but I personally don't consider those rooms to be that "nice". We have stayed at Mirage and we love the rooms and the property. But I do consider it a higher end hotel, as the average rates are generally over $120 a night.