1. should the case be silent...
2. whats your budget
3. Aircooled or watercooled ?
4. Aluminium Steel or Plastic ?
5. What size do you prefer...
1. Quiet is better, but as long as it's reasonable then I don't mind.
2. No limit. I'm not going to spend $600 on a case that is only slightly better than a $200 case though.
3. Primarily aircooled. I don't overclock to insane levels and can't see myself using more than 2 GPU's before just buying a better card, so efficient air cooling has always been preferable to liquid. The option to do it is a plus, but not necessary.
4. The less cheap plastic the better. Plastic doesn't inherently bother me unless it's the "bendy" type, but super cool and hipster case designs are a big turn off as well. I don't care about Steel or Aluminum. I do not need it to be light, easily movable, or survive a roundhouse kick from Chuck Norris.
5. Full size. It would be a hard sell for me to buy a mid or otherwise small case.
I've looked at some Lian Li cases are they appear to be made much better than many run of the mill cases available, but don't seem to offer anything anything of great importance for the added price that I care about when compared to the "flagship" cases of other major brands. The cases that I've looked at are smaller by an inch or two in depth and width as well.
I haven't looked into detail at the Silverstone cases though, so I'll have to add that to my list.
Personal tastes also matter. Do you like a case that is lit up like a christmas tree inside and outside, or do you like something less fancy?
Less fancy. I don't care about LED's or windows. I'm not in a dorm anymore and have outgrown the need to show off the expensive things I own. Except my cars. 8)