For me it is Turtle Waxes-made (supposedly) Zymol`s Cleaner Wax. Don`t EVER try to apply it with a PC-DA. Nothing but dust.
I LOVE most of Meguiar`s because they available over-the-counter, BUT:
1) Early version of M105 that dusts like crazy. I know using a spritzer of cool water on the pad seems to be a "help" to resolving this problem, but I am not enamored with it. I mix it with the consumer-version of Ultimate Compound, which helps, just so I can rid of it.
2) Meg`s consumer-version of Water Spot Remover. Again, I may have an early production version of it, but on a black Ford FreeStyle, it just swirled the heck out of the paint. I use it for windows now, which is pretty good for removing water spots that occur from 2-bucket washing when hard-water is used. Summer temps and winds just evaporate the water too soon, even in the shade, so Meg`s WSR does help in that department.
3) Early version of Meg`s Ultimate Black Trim Restorer. It was gooier that anything, needed to be applied with a foam pad by hand in the proper amount, and on certain trim is just streaked. I see some are STILL having problems with it with the "updated and improved" version currently out. it is better, but I may have to try the Detailer Line All-Season trim Dressing suggested by others.
One area that REALLY needs to be emphasized for newbees is to buy quality microfiber clothes and towels. Cheap microfibers for product removal can negate all the hard work you put into trying to perfect an exterior or interior surface, depending on the paint type/quality or material composition. I may need to start a thread on this subject, but suffice it to say, trying to pinch pennies on this detailing item can have huge consequences concerning the appearance of vehicle, which may be why a newbee`s attempt to emulate a pro`s detailed vehicle seen pictured within this forum is impossible to duplicate. The adages of "You get what you pay for" and "Penny wise and pound foolish" are truisms when purchasing quality microfiber.