I highly recommend the ceramic screens. They change the vape signature and it's quite pleasant imo. I haven't used them in a while (busy testing some other things), but I would say overall they make the vapor a little more thick, though depending how you use them. I've experimented using them in all sorts of ways, including putting 7 or 8 in the chamber with the stock MP and vaping just a tiny bit ground up, far away from the heater. It actually worked! (Though with 7-8 discs, it made the vapor less thick and the session longer, the extra ceramic changing the heat signature). One of the great things about using the discs is that you can easily make sure the load is secured in a certain spot in the chamber, whether upside down or not. Just add enough discs until it fits snugly with the rest of the load.
My favorite way to use them was to just take two, an e-nano basket screen, and the TonG. I'd put the basket screen on the bottom of the HA chamber, then place a ceramic on top of that, then the load, then another ceramic on top. It becomes like a suspended ceramic bowl for the HA. This is with the TonG, making sure not to pack it too hard because the weed will get stuck to the hot ceramic, making it harder to clean and/or the ceramic may get damaged from being pressed in too hard to the basket screen (I make it so everything fits snugly, but not that it takes a lot of force to close). Another good way to use it is just with a 1 ceramic disc on the bottom, weed, 3 discs on top, and the TonG on top of that.
A couple words of caution, they are very porous so when cleaning them with ISO make sure to give them some dry heat in the HA before using, to make sure all the ISO is evaporated. I put the disc in after cleaning and blow in the intake hole, thus giving it a hot air bath. If I were buying a new set, I would also be a little more careful with them. Once you've used them with oil for instance, they are very hard to get back to their new quality. Even for just flower, it could be a good idea to put in some loose screens in between them and the load. The DBV screens I have fit perfectly in the HA chamber and sometimes I'll line the ceramics with a couple of steel screens. If I had done that always, I'm sure those discs would be looking pretty good. In any case, ceramic isn't something that lasts forever in this application, and $12 ain't much for a nice addition to the vaporizer. I'll be buying a new set for myself in the near future.
Another cool thing about them is that you can take the screen out the TonG or regular MP. Since the discs are screens themselves, it makes for a lot less maintenance of the unit.
edit: Keep remembering good things about the discs: If you load the unit when it's fully heated, and put the discs in as a "ceramic bowl", it lets you load the weed in without exposing it to as much initial heat, as the room temperature discs take a while to heat up, ceramic having a different heat curve than say aluminum.