Opto 22 good or bad?

We are planning on another upgrade, threfore another PLC. The choice at the present is either a AB ControlLogix platform (L61) or Opto 22.
Our IO count is
34 Analogue PID loops
Dig Input = 27
Dig OUtput 56

The advantage of the Opto 22 system is the hardware and software cost.
The advantage of the AB platform is I have used ControlLogix therefore know that it can easily and reliably handle this.

The programming will be done by a 3rd party so learning the Opto flowchart language is not needed.

I read the past threads on the Opto that people have reservations on their quality (esp the IO) and the lack of online editing.

The required loop update rate would be between 100-500 ms (usually closer to the 500ms mark).

The Operator interface will be on PC's.

creativepaper said:

The advantage of the Opto 22 system is the hardware and software cost.
The advantage of the AB platform is I have used ControlLogix therefore know that it can easily and reliably handle this.

[snip]

The Operator interface will be on PC's.

Click to expand...

Amortize the cost over the expected lifetime of the system, and I'd imagine you aren't looking at very much in either case.

Then consider ease of expansion, and HMI communications (to whatever, SCADA, PanelView, CutlerHammer, Red-Lion, whatever).

I'd go with the Logix myself.