My advice when purchasing anything, as Kevin Rutherford would say.
"Look for a reason not to buy it!"
Make sure it has exactly what you want, if you want ten HDD mounts, you'll narrow your results down in a search queue rather quickly. Make a list of what you want out of your case, and remember. You may end up building several systems in the same case, so the more you spend now for a higher quality case, the longer it may last you.
Right now, I'm thinking of reasons not to get a 900D. Only two I've found are the price and the size. Price being more of an issue but considering that case could last me ten or more years, I can live with $3xx for a case easier than I could $600 or so for a caselabs case.