You will note that the IMPs are more expensive, and that is for good reason.
Many of the newer AKBs are equipped with the same mortise inserts as IMP. AKB is a distributor of various independent artists whereas IMP is a workshop. Some of AKB's pipes are by artists that work for IMP and are of great quality. Kenan and Ali are independent carvers who often supply AKB with pipes to sell that outclass all of my IMPS.
Kenan
Ali
AKB also sometimes gets in pipes from apprentice carvers. This one came from AKB and even the carvers I regularly talk to have no idea who carved it. Coming in at 12 inches with a chamber depth of 3 inches, it was nearly $70 less than my least expensive IMP.
Then we come to this no name. Flawlessly drilled with a true lattice carving, it's easily my favorite meerschaum.
Equating quality with price or brand can sometimes cause you to miss out on some very well made pipes. I once had a Baki dublin that I found very disappointing after finding that it had a terrible draw after many comments of how high quality his pipes were. I do really enjoy IMP but with their recent $40-$100 price increase, I'll likely not buy another.