I've been going back and forth between the 2.5 ohm SLB cartomizers from Madvapes and the 3.2 Boges myself. The 2.5 ohm does run hotter and in general tastes/performs a little bit more like a standard 510 atty than the higher resistance cartos do. I definitely prefer cartos to carts/atomizers with the exception of occasional dripping, but I'm not sure yet which of the 2.5/3.2 carts I prefer. The 2.5 ohm ones have a more aggressive throat hit and better vapor production right out of the box, which is great, but I find that they have a greater tendency to get into the "burnt vapor" taste. They are a little bit "fiddlier" for lack of a better term and I feel like you really have to keep them drowned, which are both things that I did not like about the cart/atty setup. The 3.2 carts, on the other hand, have great flavor and last a long time without any fiddling, but sometimes you have to push it a bit to get an acceptable TH and vapor cloud. I think on the whole I may prefer the 3.2s, but it's close and it's good that you ordered the 2.5s to try.
The low resistance ones, I don't have much of an interest in trying, but I'd like to add the genuine Joytech and the new E2s to my comparison list at some point.