This is a hard call, 'cuz $300 is a lot of money. So, here's my compromise. Buy the bike from the other store and spend the $300 on other stuff, like clothes, new saddle, better pedals, etc., at one of both the LBS's you've have good rapport with. This way, you'd put the $300 that would have spent to patronize your LBS's to your LBS and established a new relationship with the store you've bought the bike from.
