First of all, welcome to the forum
My first rack case was one of these

This was great, until i realised i was putting my back out. they weigh a lot on their own without anything in them. In mine I had a Furman power conditioner, Korg DTR1 Tuner, Samson Wireless receiver, Marshall 9100 power amp (weighs a f***ing ton), Marshall JMP1 Pre-Amp, and a multi effects processor (probably my old Digitech GSP 21) all this together with the case was just stupid heavy. It took two of us to carry it at gigs.
Long story short, I then bought an ABS case and haven't looked back. Unless you're in a touring band, leave the semi-flight cases alone. If you're just a gigging musician an ABS is more than adequate.
I've split mine as the power amp is heavy on its own so I have the power amp in one case, and all the other goodies in another case..... Like this

I've made patch panels for each case so wiring at gigs will be super fast, i'll have just 1 multicore snake from the pedalboard to the rack, and 2 power cables
This makes it much more easier to lug around, as the power amp can be carried in one hand.... The effects case at the top is not heavy, just bulky. It can be carried by just me. And also setting up and breaking down is really fast now I've simplified the wiring.
Any questions don't hesitate to ask....... I've just finished rebuilding my rack from the ground up so am more than willing to give you advice with various bits and pieces around building a quiet rig. You can read about my rig build here
viewtopic.php?f=9&t=7272Further advice also, would be whatever you intend to put in it..... Add 2 or 3 extra spaces. say you have 4 rack units 3 are 1u, and 1 is 2u, i would buy an 8u so you have a contingency for when/if you purchase more equipment. I have 2 spaces left in mine, the bottom 2 spaces are going to be for stomp boxes. I have a sliding draw on the bottom which wasn't expensive.... It was one of these
http://www.ebay.co.uk/itm/1U-19-inches- ... 3ad12cec04I've seen really expensive ones, but you need not pay through the nose to get a good system.
The rack case I bought was one of these
http://www.ebay.co.uk/itm/Pulse-10U-19- ... 3f4721c040Again, not too expensive, it does the job. You can get more expensive ones with shock mounts etc but again unless you're in a touring band I'd leave those alone.
Andy