The XTX200 is a fantastic regulator. Apeks is a highly regarded company. I owned a XTX100 (internally very similar to the XTX50 and XTX200) and it was a great reg. The XTX40 has less adjustment than a XTX[50,100,200] second stage, but should serve you fine. You will absolutely not be disappointed in the performance and reliability of the XTX200 (the TX100, an earlier model Apeks, was used in the deepest dive on scuba -
1000' - without difficulty). Most modern regulators will breath fine if adjusted correctly, you usually pay for reliability, customer support and occasionally just for a brand name. The price, even for Apeks, seems a bit high to me.
You might consider a
HOG D1 setup which is very similar to an Apeks reg for less than half the cost you're quoting - and with two identical second stages. You'll have to buy the 2nd second stage separately, hoses too, but Dive Right in Scuba will assemble them for you if you ask. The whole package will run you about $400. It's what I'm diving, it's what my dive buddy is diving.
Octo-inflators (Airsource3 and similar) are a highly debated topic. There's an extensive thread on the first page of this forum
here, and I'm sure if you searched you could find more. Many people, myself included, don't care for them. However, I know at least one highly experienced (and extensively mustached) diver that uses one for every dive - and he's done everything from scuba accident investigations to scientific diving under the ice at the north pole. Do a drill with one and choose for yourself.