Purchase a widget that costs 10 BTC and will generate 400 BTC, valued at $2 each or
Purchase a widget that costs 10 BTC and will generate 5 BTC, valued at $200 each
Invariably, the answer will be the second option, even though that person could have increased their BTC holdings by 40x! Very few people want BTC for BTC sake, they want BTC for what value it provides in their local currency. Again, you may be different, but you are in a very tiny, miniscule minority.
Ok, you give me 400 BTC and I'll give you 5 BTC. We can use John K. for escrow if you're uncomfortable with the trade. I'll even pay the escrow fee.