Mike, if you are building from scratch and have the skills, make your own road dropout but make it closer to horizontal and as long as a track end. Then you get the best of both words (as long as you are not so strong that you need more than a wrenched nut to keep the wheel from slipping forward). You have a slot long enough to allow multi-tooth cog changes without messing with the chain. And you get to have dropout screws that you can set to the correct chain tension. Then, voila!, you no longer have to work to get the chain tension right. (Also your wheel comes out forward so you do not have to take the chain off until everything is good and slack and it is easy. You can even have a slot that goes forward, then down, allowing the forward end to position the tire right next to the seat tube and still have an easy wheel pull. Add a chain peg on the seatstay like any road bike and use a Pedros fix gear tool and you can do clean-hands wheel flips easily.

Ben