Do aftermerket crossovers improve sound?

A company called Northcreek sells aftermarket crossovers for B and W 8o2-matrix series 3. I own a pair of these. These aftermarket crossovers are Quite expensive. They actually cost just about what the speakers are worth.Northcreek claims that these crossovers will make a very noticable improvement in the speakers sound. Is this just snake oil? Has anyone out there invested in these? I cant afford new speakers because of the economy so I was considering purchasing these.
Shadorne amazes me how much folks pay for cheap transducers and poor measuring crossover parts. As long as it has the right brand name or had a + review fancy veneered of coarse. I see many 15k loudspeakers with $50 tweeters. In our KCS 17K model we offer fostex amk2 a $1550 tweeter set. Our capacitors cost more than most all parts used in out competitors loudspeakers. But your right many folks do not buy on quality of design and parts just on validation. There loss.
Give Bill Legall of Millersound a call to see what he can do for you;he is one of the most regarded people in the industry for speaker repair and crossover redesign.
The simple and straight forward answer is yes. Speaker manufacturers neglect the internals of speakers when they are trying to keep costs down. They know the 90% of people aren't even going to look inside.

Even if you just replaced the critical parts on the xover, it would be a great improvement. When I upgrade xovers, I focus on the high and mid parts, a lot less to be gained from the low portion of the circuit. Furthermore, I typically just swap out for like values, and only on ocassion, do I bypass caps.

Bottom line, it's right up there with the best money you'll spend on audio.