If you're not going to resleeve, and you're building an N/A B20/VTEC, then you could probably do it for less than a resleeved B18C with an LS crank and rods. However, most people don't take the time to build them the right way. By that, I mean they usually just take a B20 block, and slap a VTEC head on it and call it a day. Built as such, a B20/VTEC will not hve a very high level of reliability. It won't be able to rev as high as a B18C, nor will it be able to do so safely. People don't take the time to install VTEC oiling components, and they often try to install a block girdle by simply bolting it up, which does more harm than good. To properly install a block girdle, you need to machine dowels in place. It's a fairly involved process, so it's just a lot easier to start with a B18C block and swap out the crank. If you're building for boost, then a resleeve is oretty much required, so why not just resleeve a B18C and have the OEM VTEC components already there.