I've never bought a gun on impulse. When I finally make up my mind, the search is on for the best price from a place I desire to give my business too. Buds has a great reputation and regularly the lowest prices on the whole of the internetz... not always, but regularly.
I've bought 4 guns from them and for each one I waited about 2 months before buying. I watch about a dozen major websites and hit my LGS's to gauge what I should pay, set a price, and wait. But I always give my LGS the opportunity to earn my business, which means they don't have to be able to beat the online price... maybe we also work a deal on accessories or I just feel like it's worth the extra dollars to get it that day.
Once I know my LGS can't/won't meet my price, I just sit and wait for a deal... free shipping, 10% off, rebate, free t-shirt, free ammo w/purchase... sooner or later, I buy.
Buds prices on "in-demand" firearms can/will go up or down daily... sometimes a buck or two, sometimes $20 in a week. I bought an R700 a few months ago for $604 shipped... a week later it was $589 shipped. Shouda waited?
The "make an offer" is a great idea... and yes, some guns only come down a dollar or three, but being Buds, it's probably the lowest price to start with. Find a gun that Buds is asking more for than other places, and offer it down... or try your offer in a week and see if the computer that runs the pricing scheme likes your digits.