I have Lipert slide mechanism, so I can't comment on the Schwintech. My slide has been trouble and maintenace free.
What I will comment on is roof maintenance. In my experience the actual membrane material requires very little maintenance beyond occasional cleaning. The required maintenance is on the seals (caulking)...you will still need to be vigilant in your inspections of these seals regardless if you EPDM, TPO or a Poly/Vinyl that you mention. Warrantly DOES NOT cover seals/caulking beyond 90 days since they are considered a customer maintenace item.
As Waggs mentioned, its much easlier to find issues posted online opposed to compliments. However one thing seems to remain constant, the folks who encounter issues with their new Jayco RV are taken care of by Jayco with little fuss. The selling, or servicing, dealer is often the bigger headache. If you have a good dealer and like the unit I would not hesitate to purchase. If your dealer has a reputation to not provided great service after the sale, or if you plan to get service from a local dealer who didn't sell you the RV, that would be a bigger concenrn for me over the roof membrane or slide mechanism.
2007 Chevy Duramax LMM/Allison
2012 Jay Flight 29QBH
2012 Jay Flight 26BH (Sold)