Just to confirm everything Europa said is spot on.
Have FK Konigs made by Koni to FK specs on a Veccy. Fronts are easy to set up inc ride height and rebound etc. The back are a real pain to set the damping as a pair as there are no clicks, just rotate the shaft. The only way i could set the damping was to put a weight on the damper in a vice and time the compression- As things warm up the compression speeds up making it even harder to balance out. 2-3 hrs later.
The backs are set on lowest balanced damping/rebound- harsh but tolerable all round except country lane C roads.
Fronts ended up with max damping/rebound, ride height not really much lower than SRI and also its harsh on anything other than a smooth surface. Bump stops reduced by 1/2 of standard suggesting minimum travel. The springs are superb quality but the rebound on anything lower than 3/4 of max possible borders dangerous on bumpy A roads. like being in a speed boat.
What i did find out quick was literally 1 revolution of the ride height 1.5mm will mean the difference between being tolerable or not. The only way to find out is to understand what goes on and take it from there. Basically you wont have much suspension travel and the supplied springs will be really progressive meaning they go rock hard within a very short amount of travel. Its just finding the sweet point or more importantly whats tolerable. Imagine longer travel suspension, can have weaker springs for the same given absorbtion rate and therefore less rebound and damping!
Also FK take at least 3 to 5K to soften up, mines done about 18k and need raising about 2mm, easy job 5 mins. Might try some softer springs!
I wish i went for Koni Sport the adjustable top damping front ones £200 less, had em on last car certainly for the type of driving i have to do.
As for the cheapies, forget them. When i was deciding i specifically asked the manufacturers whether the rebound was uprated not the damping (being non adjustable.) Every single one avoided the answer or didnt know! Spax were like that adj damping with no increase in rebound.
All coilovers will be the same, some a lot worse than others. If you just potter around town cruzin (look at me) just the job. If you drive even normally you will regret.