Probably a good guideline. I ran a pick up game at a convention over the Labor Day weekend, and one of the players was one I knew. What I knew about her was that her PC's equipment list would in no way conform to the recommended budget.
What shouldn't have surprised me, yet did, was that she had about 110% of the recommended budget invested in a single item, a magical bow. It was less than half of her total equipment (meaning that she had more than twice the equipment allowed), but it was still a problem.
If she'd been using it in a combat, instead of an RP scene archery tournament, I would have been tempted to Sunder, just because, but it didn't play out that way.
What was hilarious was all the character quaffing Dex potions and using scrolls worth hundreds of gold pieces in order to win a 5 gp medallion.
On a fiendish-glee type of side note, the actual conflict began after the tournament was over. Then the players looked at me in shock as they realized how many spells and consumables they'd burned through, and hence didn't have instantly available for combat. Lots of low level spell slots gone just when they needed them, almost as if the DM had baited them into such foolish expenditures on purpose.