I agree fully with the last two comments. Bourbon by (legal) definition is all similar - yes, yeast type, mashbill composition, but most importantly, aging, will differentiate them. But provided you can buy one not too oily/corny, it is as good basically as any other - I said basically or in its essentials - and sometimes, or in the view of some that is, better. E.g. recently I served a friend, not a bourbon fan as such, Rock Hill Farms (about $50.00) and VOB 86 ($12.00). I served them blind. I said, which do you prefer? He said the RHF, because it is "smoother", i.e., presumably, has less flavour and palate impact. Well, I prefer the VOB. It tastes more like bourbon whiskey to me, it has a full fairly complex palate. The other is drier, less complete in the palate IMO, thinner in body too despite the higher proof. Hey, that's my opinion, and many here may disagree. But the point is, it's all good except, IMO again, very young stuff that hasn't lost a strong oily edge and is almost like corn whiskey.
Of course some wish to spend more for a more aged (woody, smoky) taste, and that's fine. But that's more on the details of the drink, not to minimize them for enthusiasts, but the basic profile of all bourbon aged 4 years and more is similar IMO. And you can get many 4 year old bourbons, and older in some cases, for a low price, many brands have been mentioned in this thread.
Also, I stress that some private label brands - they are getting harder to find but are out there - are excellent values. Banker's Club is one.