(System Spec's posted at the end)
I am looking at the HDSPe AIO and have a few questions:

1. Is there a physical volume control option to control levels to the XLR Outputs (monitors) and Headphones? (If not, what needs to be purchased?)
2. Is there a 1/4" input for electric guitar/bass/etc.? (If not, what needs to be purchased?)
3. Will I see a significant ASIO performance/stability increase with the PCI-E card vs. a USB 2.0/Firewire interface (i.e. Babyface Pro, Fireface UCX?) when primarily using a significant number of simultaneous VST instruments within Windows Cubase 8.5? (VST orchestral projects with 50+ tracks)
4. (in relation to Question #1) Is there a desktop extension box that interfaces with the HDSPe AIO that gives it a similar form factor to the smaller Madi/Firefaces (I/O, volume knobs, etc.)?

System Specs:
CPU: Intel Core i7-4930K 3.4GHz 6-Core Processor
Motherboard: Asus X79 Deluxe ATX LGA2011 Motherboard
GPU: PNY NVIDIA Quadro 410 512MB
Memory: Kingston HyperX Beast 64GB (8 x 8GB) DDR3-2133 Memory
Storage: Samsung 840 EVO 250GB 2.5" Solid State Drive
Storage: Samsung 840 EVO 1TB 2.5" Solid State Drive
Storage: Samsung 850 EVO 500GB 2.5" Solid State Drive
Storage: Samsung 850 EVO 500GB 2.5" Solid State Drive
Storage: Samsung 850 EVO 1TB 2.5" Solid State Drive
Case: NZXT H440 (White/Black) ATX Mid Tower Case
Power Supply: SeaSonic 660W 80+ Platinum Certified Fully-Modular ATX Power Supply
Operating System: Microsoft Windows 8.1 Pro OEM (64-bit)
DAW Software: Cubase 8.5 x64