I'm only NOT recommending them based on cost.
Over wattage bulbs REQUIRE the additional expense of a heavy duty harness.
That being said, the Fatboys (and Rampage housings) are MUCH better than stock.
After 2.5 years, one of my low beam filaments died.
Since MOST of my driving is in well lit suburbs, I decided that $90 was too much so I opted for $50 Silverstar Ultras.
As a test, I only replaced the bad Fatboy.
Shining up against a wall, the Ultras are a BIT whiter, but while driving the Fatboy washes out the Ultra. You can tell the Ultra is there but the Fatboy is doing most of the work
I found some Osram 100/90 bulbs on Ebay for less than $20 shipped (!) so I think I'm going to order them and return the Ultras...
(Edit: I just noticed that the picture at the top of this page differs from what my bulbs look like... Maybe I have Fatboy 2's??)