On some things Niagara has a great price. On some things they don't. I assumed they were going to be the low-cost king (I've ordered from them maybe six times), but not necessarily. A lot of their cheap stuff is generic junk too. What drives me crazy is how much their prices move around. Bought some mini toe clips for $4. Next time I ordered them they were $8. Bought some Pasela TG for $18 in July. Wanted some more and now they're $25. They were not "on sale" in July, just $7 less.
On the other hand, Rivendell has the Nitto Albatross cheaper than any other web source I've found. But Rivendell is a boutique shop, and doesn't compete on price.