Gearbox,
If you love the look of the chrome (and who doesn't?) and, also, feel that it's just not a BSA without it, and, also, believe it must be so, regardless of the cost, then you are doing the right thing. On the other hand, if the goal is to achieve show-accepted or marketable originality, I don't think you can get there with the hybrid, regardless of the chrome. There are many beautiful BSAs with painted tanks. I think mine looks decent for a plain paint job, but there are some real gems out there. Having the hybrid opens the door for your own flair to come out in all aspects of the build and its aesthetics.
Maybe I should have have opened with the fact that I am also currently restoring a tank. In my case, the originality of the chrome would go with the matching numbers and original nature of my barn find, but I can't swallow the cost of the tank about equalling the cost of the bike, so the tank will be nicely painted. My first goal is to finish the bike while I am above ground. After that, the likelihood of me selling it is very small. Some future owner, unlikely to be my wife or either of my children, can chrome the tank if they so choose.
Richard L.