Not suprised that someone tried to sell you a burton in a shop, however you will find most online places like this one to not love burton.
Shop ppl usually have an agenda that has nothing to do with your needs. Do some more online research about boards.
Some criteria I care about, you may not:
1. I prefer handmade in the usa over machined in china
2. tech: carbon fibers, camber variant, edge profile, etc.
Its pretty easy to get a feel for things, just do some reading, this forum has a TON of info, the search function is money.
Not being a hater on burton, but I have yet to hear anything positive about them that puts their product over their competitors. Especially boards. Their boots have a much better appeal, the burton moto is the top selling boot of the last 10 years and I doubt it is because its uncomfortable. Their bindings also do well. I wear burton gloves cuz i got a deal on em and they work fine (if a little crappy on the craftsmanship).
Something to consider about burton boards: the main reason you see them on the hill is because 90% of the rentals out there are burtons.
Here are some brands that you will find alot of good things about on this forum and the interwebs in general:
Never Summer (props to the local boys)
Mervin - Lib Tech/Gnu
-to name a few
Again the advice to wait on buying a board cannot be overstressed. Boots and bindings are something that you need to have good shit, but as a beginner the board you choose is going to have very little impact on your riding for the next couple of years. Better to buy something 2nd hand or super cheap so that you can replace it or add to your quiver quickly if it doesn't suit your tastes or current conditions. If you go spend $600 on a board right now, you may or may not like it very much, and you won't be able to unload it very easily (especially if its a burton). Again not hating on burton, but speaking from recent experience/mistakes in board buying.