I would feel fine about the Monroe/Gabriel dampers. On our coupe the only time you ever noticed the Munroes were street shocks was in turn 1 which was about a 135 KPH or so corner with a big dip followed by a bump , while drifting though there the car would dance around a bit. Nothing alarming but noticeable......this isn't gonna happen in street car on street tires.

Littledarkone , the problem you are likely to have with lowered springs in the back is the piston in the damper/shock will not be riding in the area it's supposed I.E. the longer shock with lowered car will compressed , this can cuase problems. Easy solution is to find a shock that matched the spring rate and ride height.....check some parts books or hunt e-bay for some of those Koni reds.
Also I know the cheapo KYB's get bashed in some circles but I used them on a little Civic wagon we had and they made the car decent to drive were it was mush and wheel chatter before.

Tom