Well it's almost worth it. Note that I NEVER rented but here's how it works if you buy:
If you fly in, there's a few problem with bringing your own bike, which I faced. I was in Reno, mind you:
-Bikes disapear crazy fast in Reno, even walmart for those sub-130$.
-You're renting a car, you need to buy a frigging bike rack now. You then have the added stress of scratching the rental car with the bikes hanging from a super cheap bike rack. Note that the bikes won't fit inside with 2.5 gallons per person per day with 3 people in the car plus food, tent etc. Note that we flew in with all our equipment except the food, if you're efficient you can pack everything in a your luggage and still be withing you weight allowance.
-The bike is destroyed at the end of the week and it's probably full of spray paint anyway and you can't bring it on a plane.
The big money saver here is to buy a Burning Man bike from the Reno Bike Project. They take trashed BM each year and make them playa worthy again and sell them back to you for very cheap. They will even take them back afterward.
PS: Walmart bikes have a reputation for dying on day 2 on the playa, I witnessed that myself several times.
I must say the guy who wrote his experience is much more wealthy than me, I usually DO NOT HAVE A bike because I can't afford to bring one. I actually walk, which is pretty crazy if you've been there. I just scrape together the money for 1) Plane tickets 700$, 2) BM tickets 300$ 3) Car rental split with others 500$-1000$ depending on rental outlet 4)Food: whatever is left :). I mean fuck, two years ago between us we had 50$ left for 2 days in Reno for food and everything after the burn. We agreed to bet everything on the red in roulette, yes we won :).