I'm still going to argue the case for the Unilift.
I think that there is not just the issue of the lift to consider, the mounting plate is important too. As several people have said machines from Trend and Triton have a good adjustment system but you do also need to source an accurate and rigid mounting for the router too. It is no good having a big powerful router in a flexible support, it will degrade the quality and accuracy of the cut.
I can only speak about my experience with the Unilift, but it has a very substantial alloy plate with eight grub screws around its perimeter which allows very accurate levelling to the table so I get an absolutely smoothe transition of the leading edge of the work from table to plate to table with no catching.
It also comes with three very well fitting insert rings of various diameters and a further range is available as an add-on. These rings are accurately machined, absolutely flush when engaged, yet quick and easy to fit.
The whole structure of the unit is substantial in complete contrast to my earlier plastic mounting plate where I could take hold of the router and wobble it with very little effort.
The Unilift comes with a substantial brass starting pin which screws into the plate, a very complete range of screws to suit a range of different routers, a well designed crank handle which fits into two different locations and a ball ended allen key which fits the brake on the height adjustment. Another useful feature.
The only possible negative feature to be aware of is that it is is calibrated in imperial units not metric. 1 turn of the handle = 1/32 inch. Also the plate surface carries two scales allowing fairly accurate location of the fence relative to the router axis which are imperial too. I'm fluent in both so it's not an issue for me but could confuse the metric only people.
Yes it is expensive, and you can save money if you wish, but I have never regretted buying mine. To be honest, when I took it and the fittings out of its box I was amazed at what you get for the money and I'm a bit of a tight-wad!
If you are fitting this to a shop made top and time is money then a ready-made template is available to assist with machining the cut out. I made my own which took a little time to get perfect but it worked fine and saved some money. I have saved it in case it's of use to anyone else close by.
Mine came from Roger at Woodworkers Workshop whose level of service has always seemed exemplary - he did make a bit of a packing error with this order but then passed what I think is the critical test of a supplier - how they deal with a problem, in this case put right within 24hrs.
Anyway, thats just the opinion of one man with no experience of your stated alternatives, but I hope useful nontheless.
regards,
Colin