I am very wary of using clipless pedals on a fixed gear for fear that they would pop out under stress.
(like SPD's seem to do). Though I have heard good things about eggbeaters and similar designs.
(additionally jamis stocked generic but good eggbeaters on all of their mid range bikes last year and so you can buy them for a pittance at any Jamis dealer.
I would suggest that whatever you do, keep a front brake.
If you are going to run clipless I would use eggbeaters or something else that uses a similar design.
I would suggest at least trying traditional toe clips. Decent pedals, (MKS makes a nice range for very little), mated with mountain clips and a straps works quite well. I like to run a double strap, Soma makes them cheap 40 instead of the toshi 100, though you can also just run two straps.
To each their own but I recommend against SPD + brakeless.