How would this suit editing with Vegas 11 and/or 12 for that matter?

Gigabyte ATX Mobo,
Intel Core i5 CPU,
8 GB RAM,
nVidia GTX 570 GPU,
1TB 7200RPM SATA III Hard Drive,
Midi Tower Case (with 2 x 120mm fans),
550W PSU, LG DVD Burner & unit installed with Win7 Home Prem.

cost quote £790

any comments welcome

What formats are you shooting most?

Are you currently transcoding footage to an editing codec? Does that sound like a good idea or a bad idea?

Are you mostly doing cuts and titles, or complex multi-track graphic sequences?

I use mxf files from canon Xf cameras mostly..straight edits some graphics no transcoding. also some stuff from go pro and smaller format cameras

I'll have to leave the question of Canon MXF performance to someone who works with it on Vegas.

Otherwise, the machine spec seems to me to be a decent "economy" approach, you should get mid-range performance out of it. It should support cuts & light graphics across most source formats just fine, if the Canon MXF codec support is good.

Can anyone on Canon MXF comment on the processor demands?

which flavor of core i5? there are many different clock rates and different generations and they give you different raw performance. i use cpu passmark (PassMark - CPU Benchmarks - List of Benchmarked CPUs (http://www.cpubenchmark.net/cpu_list.php)) as a guide, mostly useful for comparing *relative* performance of cpus.

for example, a core i5-2500 running at 3.3GHz has a passmark rating of 6580 whereas an older core i5-650 running at a nearly identical 3.2GHz has a passmark of only 3213.

they have similar ratings for various graphics cards.