The B18's can make good power n/a, but it really depends on what you want. To make BIG power or if you're building a street/strip setup I'd say go turbo. If you want 250whp or less it's a toss-up. If you live in a state like Cali with strict emissions, you gotta boost CARB legally, which is pretty expensive. Illegal N/A is A LOT easier to get away with and is cheaper for the low 200's whp range. Once you get into stroker kits, ITBs, extreme and calculated porting, race headers, etc. turbo WILL be cheaper for the power. The biggest thing is your philosophy on cars and how you like your power band to feel
right now i got the b18 may eventually upgrade the head but that would be awhile... when my engine gets in i can put some real work in and see what i need to do first.