I'm a big fan of egos: durable and easily maintained, excellent performance, and great customer service from Planet. Ego6s are great too if you can't afford an 07. Can't offer any experience on the other markers.
The DM5 are one of the most easiest markers to service as i have 2 as backup's, stripped & lubed in 15mins, easy access to all the parts, & you can pick one up for around £150.00...
also can sombebody post me some kind of info or website where there is info on the FEP Quest as i cant seem to find out anything about it and to e looks like it ripps