Anthony has recently turned me on to Top Of Line's Best Dressed rubber and vinyl dressing. I dilute it 3 parts water to one part dressing for a rich satin look.
If you go full strength with the stuff its super glossy. I dont like the super glossy look so I dilute it but I have heard fo guys using it straight for really glossy tires.
For high gloss, I use Einmann Fabriks Black Opal dressing. I got gallons from www.properautocare.com and I am not even thinking about trying something else, I love it.
I would try the EF Black Opal, I personally like the Black Saphire because I prefer a gel. With the Black Saphire I can control the amount of gloss that I want to achieve, I usually keep it low.
Not sure about Vinylex for Gloss, for me it is a very low gloss tire dressing.