The down side is, there are certain thinkg you should equip it with, or have done to it. So between the added parts, and the slightly more cost of machining work, they end up about 10% more expensive. The up sides are: ease of interchange. You have everything it needs..brackets, mounts, etc; Power curves that best match a street driven car; Manners that make it much more suitable for a street car; Visually it is indestinguishable from the base enigne you start with. In terms of value, the 360 based egnines are the cheapest. In terms of max power possible, the 340 would ge the nod from me. If you have a good running '69 340, even un-rebuilt, it has a bunch of value. If you are truely looking for a fairly simple build, find a 360 core from a mid 70s truck. If you are looking for cruiser, and you can abide by the rpm limits (under 5500), there are more piston options in cheaper types, and factory rods can be used, cutting the cost a bit. The iron heads will support it cdecently to about 5500 anyway. Beyond that, you need to either buy some porting or buy better heads. Also, you will need to buy a bigger carburetor to fed it. Bigger than you might normally budget for. You could sell the complete runnign 360 for about 1/4-1/3 the cost of a nicely built 5500 red line 408.