Hello GearSlutz users

Please skip the blue parts to avoid backstory and get into the good stuff.
I have been a watchful ghost on this website on and off for around a year and a half now. I have usually found the answers to my recording questions by searching this website and reading through the various arguments, opinions and confirmations within the community. I am on the verge of a financially huge commitment, with my previously described tactics of research not yielding the usual results. It is for this reason I have decided to create an account, and ask the GearSlutz community directly for their greatly valued opinion.
I am well aware this thread will cause some users to be less than pleased, and I am happy to be directed elsewhere to find answers should this be possible. The "what Mac should I buy" question is a frequent one, but I feel for good reason. Allow me to explain my position;
I currently run a very old PC which still boasts Sonar 7 as the primary DAW, and made use of software based vst instruments and effects. Not much outboard equipment was used at all as it was more used for MIDI composition and occasionally audio projects consisting of acoustic guitar, drums, bass, piano and vocals. I am now in a much better paying job, which has finally allowed me to save up the money for the Mac Pro I've always wanted since recording on them at college and in local two local studios.
Being a firm believer in "you get what you pay for" so have saved up the big bucks for a really nice Mac Pro, but have been told by another engineer that I may be buying too much Mac for my money!? I am told that the set up I intend to buy may be overkill, for example, paying out for a better processor is unnecessary since the lower spec processor can handle the same jobs without struggle, rendering the higher spec processors redundant with nothing to process!
My question: "Is this Mac Pro overkill for what I need?"
The Mac:
Two 2.40GHz 6-Core Intel Xeon processors (12 cores)
12GB (6X2GB)
1TB 7200-rpm Serial ATA 3Gb/s hard drive
ATI Radeon HD 5870 1GB
One 18x SuperDrive
Software it will need to run:
(Audio recording is priority, with VST instruments being used mostly for compositions)
Logic Pro 9 / Final Cut Pro X / Native Instruments Komplete 8 /
PRICE: £3,273
That's basically it, I will have outboard compressors, reverbs and so on and mixing desk will be on the bill too, but as far as software is concerned I would like your opinion on this Mac Pro versus its "little brother" of the following spec;
Mac "2"
One 3.33GHz 6-Core Intel Xeon processor
12GB (3x4GB)
1TB 7200-rpm Serial ATA 3Gb/s hard drive
ATI Radeon HD 5770 1GB
One 18x SuperDrive
PRICE: £2,629.00
I would once again like to thank you in advance for your insights, I have always valued the GearSlutz community, let the discussion commence! Further details available on request
Thank you!