How to hook up Op-1 and Moog sub phatty and ableton?

Hello all, im a almost 2 years owner of the op1 and I’m going to get my sub phatty in the mail in a couple of days,

I chose sub phatty over the sub 37 because i was thinking the op1’s arpeggiator and sequencer can compensate the cons of the phatty (compared to sub 37)

so here’s the question,

How can i send midi data to the sub phatty whilst linking both synths to live 9?

I was thinking about a usb to midi cable like this one http://www.amazon.co.uk/Roland-UM-ONE-mk2-MIDI-Interface/dp/B00967UN50/ref=sr_1_1?ie=UTF8&qid=1418259605&sr=8-1&keywords=usb+to+midi+cable

but I’m not 100% sure that will work, given my bad experience with the op-1 in the past

do i need to buy something like a oplab or a sbx-1?

and that brings another question, I’ve heard some bad things regarding the oplab, indicating issues e.g. not syncing, crashing after 5 minutes etc. is the oplab very unreliable? plus the sbx-1 is expensive and I’m not even sure if it will work on the op-1, and I really prefer to spend as little as possible on accessories.

Thanks in advance!

another question, if i send midi from the op-1 (2 octave keyboard) to the sub phatty (2 octave keyboard), can i get a play range of 4 octaves?