I used the SPS, for the first time, this weekend. My last two cakes fell and I was terrified to have another go this way (first time in 15 years). The package arrived 2 hours before delivery! The system was great and worked perfectly!
I made one mistake that I would share, I measured the tiers from the top of my turntable to the top of the cake. Oops! That made each plate sit above the cake since I should have measured from the top of the cardboard cake round!
Luckily, the entire cake was covered in coconut, so mistakes were easily fixed. My 8 inch cake also cracked, but it was still cold when I pushed in the columns. I'm sure it wouldn't be a problem for a room temp cake.
Two benefits I haven't seen mentioned so I'd like to add.
#1 Placing a cake on top of a separator plate is 100 times easier than trying to center and stack a cake with spatulas and extra hands. As mentioned, the cake is also even! No leaning tower of cake that is impossible to fix once you have it tiered.
#2 Once the plate and columns were inserted into a tier I was able to pick up the cake between my thumbs and fingers, by touching the plate on top and the cardboard on bottom. NO touching the frosting. Im sure it helped that the cakes were still cold, but I think it would be the same for a room temp tier.
The cake had to be moved from the display room to the cutting room and it was easy peasy!! Even the caterers were impressed.