Hello Rob.
I have a pretty good deal of experience in both home and studio recording. Nostatic's modular approach with the Presonus, Logic and Mac is a pretty good way to go. This is a standard type home/project studio, which is good because you want to learn and utilize software that is powerful and somewhat familar in the industry (Logic). The most important thing is that his setup all works together, probably pretty flawlessly, no driver issues, system hiccups etc.
Personally, Im not crazy about the MOTU converters, but really its not the converters in these systems that is at fault...its the system clock.
In a prior life, I was the National Sales Manager for Aardvark Digital Audio (a company no longer in business because their stuff didnt play well with others aka driver issues).... but one of the things Aardvark did famously well was Clocking.
I use something called the Aardvark AardSync II to clock my rack. The converters (A/D and D/A) use the Aardvark clock as a reference as to "when" to precisely take a sample... this is extremely important because the accuracy of the samples is what gives you the digital representation of the analog audio wave form, most accurately (speaking in laymans terms).
At Aardvark we had one of the most accurate clocks in the world, with some proprietary clocking technology that really made the converters work more efficiently and Sound Better.
Now, my reason for bringing this up is that if I were you, and were putting together any system...I would consider purchasing an external clock (such as Apogee Big Ben, Lucid Audio Clocks, Rosendahl Nanosync etc.) to clock the rack with... as this will help to make "pro-sumer" gear sound more pro. If you do go this direction though, which I personally recommend, you need gear that accepts Word Clock In or S/PDIF in that is clockable.
Looking at Nostatic's rig, Id guess that he is using the superior clock in the Apogee Rosetta to clock everything in the studio to. This provides solid word clock sync for the studio and probably makes his MOTU inteface sound better too. Nostatic also has some pretty sweet mics and mic preamps etc....all of which will make a huge difference when he crafts his sound.
Back to digital audio workstations... if I had to start a studio now (and I am considering tossing my PC stuff and going Mac) I would go Pro Tools. The reason for this is that Pro Tools has long been the industry standard software, and probably always will be. If you know Pro Tools, you can walk into virtually any top studio in the world and know how to throw up a mix or lay down a track (very important if you ever want to do this for more than just fun).
Pro Tools has a selection of lower cost pro-sumer gear such as the M-Box 2
http://www.sweetwater.com/shop/pro-tools/
which works with their Pro Tools LE software.
If you are going on PC, you could consider using M-Audio gear a company which has been around for years and is known to have solid working drivers and a wide array of products. Give the guys at Sweetwater a call...they know digital recording very well and can recommend a good system to fit your budget.
If $600 is your budget, then I think you can get a decent system but not nearly as good as if you spent a grand.
As for software, in general Cubase is very good but has a steeper learning curve...I like Sonar as it has good capabilities especially on the PC, but its considered pro-sumer in the industry (if that type of label means anything to you or doesnt matter).
There is NO such thing as zero-latency (however it is compensated well with the better interfaces and software). Physically its impossible. Even me playing a guitar through a cable to my amp has latency. Every computer recording interface has both internal latency (very very small and not noticable)...and latency that builds as the tracks are recorded and played in the computer. The most powerful DAWS compensate for latency with a combination of software delays and DSP chips. You wouldnt notice it untill you were playing back 12 tracks with some signal processing and effects on a PC with limited power and RAM.
for more info, check out some of the forums on the web such as
www.homerecording.com or
www.audioforums.com
another good retailer in addition to sweetwater is
www.audiomidi.com (they know their stuff pretty well there)