I've used e604's primarily on drums for both live sound and studio recording with the college I'm at and the clip on style rim mounts made it easy to set up. However these aren't clip on mics like the e604's, these clamp on instead which resulted in a problem when trying to attach to my snare (Tama SLP Power Maple) as it would only clamp on a diagonal rather than being vertical so a I had to use a mic stand instead, all other drums were fine.
The sound from these however is not unlike the e604's, they have a very good definition of stick attack and drum tone albeit it a bit loose on the resonance after the hit but with simple processing these can easily sound as good as anything you'd hear on an album.
My only real issue with them is the clamps themselves. The clamps are stylistic and curve inwards at the bottom then outwards at the top, this created a problem as I would usually have them closer to the heads for certain styles but in doing so (especially on rack toms) the mic ends up to close to the drum. The solution to this was to place the mics higher up the clamp (which is still a bit too far in for a 10" tom) and place them more on axis than usual which isn't the exact sound I desired from placement.
These are also more versatile than just drum mics, I've use both the CD55 and BD-200 to record guitars and bass with a very good result.
Overall these are great sounding mics on a budget and while a better clamp design makes it somewhat ill-efficient to what it is capable of you can't go far wrong with them. They are very well built, especially the BD-200, sound better than most other mic packs below £150 and are versatile enough to work on other instruments which is handy if your on a budget and can't afford a mic for each situation.