The problem with acrylic facemounting is the possiblity of bubbling/outgassing from the acrylic, since it is a hygroscopic material, hence my preference for avoiding it. Some labs also facemount to glass, but that has its own issues in terms of fragility, especially during transport. As yet, no-one facemounts to a UV-blocking Gorilla Glass...
Gorilla Glass is considered for cars now so it may take some time before it is used for face mounting but not impossible.
"Digital" face mounting behind Gorilla Glass is most likely the real future, from phones to wall size choices :-) Then your quest for super gloss is solved too without the cons of super gloss like display lighting reflections, delamination (could happen though but you have a warranty), not mounted plane enough, etc. The pros are numerous to mention all; no need for a face mounting shop, better dust control in mounting than any face mounting shop could afford, no spraying needed, no OBAs, wider dynamic range, easy to change media behind the face mounting, not plasticky but true glass, no harm done to the image if the glass is not as strong as advertised, display color management to compensate RGB dye bleaching, images can be transferred fast to odd exhibtion places on the globe, etc etc. A big disadvantage is piracy though ..........
There are some good Diasec face mounting shops. Sometimes the shops see things happen with their face mounted prints that have to do with the printed media being changed without notice, bad batches, etc. Go by their recommendations, Wilcovak in The Netherlands face mounts inkjet matte art papers as well, without the extra film lamination that RC inkjet papers require before the face mounting step. They train other shops in Diasec mounting, you will find the addresses at the Wilcovak site. There are still issues like OBA burnout and possibly the dark storage issue where RC prints that last well in (reduced) light can get darker when stored and regain their original tone when exposed again to light but not always totally. The longevity of face mounting is subject to debate, there are some PDF reports on the issues (variety of shop methods though). Expensive face mount prints are sold everywhere as you know, it is an accepted medium. I have seen a Dutch (semi-official) intention to test face mounting years ago but no subsidy left I guess so no results yet. Who knows, maybe we will see something done after all one day.
If it has to be super gloss, super clear, face mounting to cast acrylic is hard to beat if not impossible.
Met vriendelijke groet, Ernsthttp://www.pigment-print.com/spectralplots/spectrumviz_1.htm
December 2012, 500+ inkjet media white spectral plots.