We use alot of Alerton controllers on my site (400+). I personally like the way the software interface's with the hardware. The hardware seem's to be solid so far 2 yrs running. Also my local Alerton rep is top notch with by far the best customer support I have expierenced so far.
I also like the way the controllers are programmed. Envision which has replaced backtalk uses Visio for the programming engine with a few of alerton's plugins. The view live data function makes troubleshooting a breeze. So yeah I have a few opinions of Alerton and most of them are postive so far.
The first picture is an example of the programming.
This picture is of the controllers and transducers for a hot water converter controls
I specify them on every commercial job I design. Owners love it, very simple to use.
The pro's are:
easy to modify graphics and schedules
trend logs are "weird" it randomly picks a time and date
scale on trend logs is one scale so if you are trending temp and CFM on a RTU the temp scale is out of wack
on the RTU screen it doesn't tell you what the alarm or warning is, it just says alarm or warning. You have to go the the RTU to see what the alarm or warning is.
I've found the key to using Alerton is the set up. If your rep can set it up to your specs it is great. If he can't it can be troublsome.
All in all it's easier to use than Tracer Summit and can be modified to do just about everything.
Alerton makes an excellent product. Novar bought Alerton and Honeywell just bought Novar - so the future of the product is unknown, however the rumors I've heard are that Honeywell will not tinker (at this point) with Alerton's lines.
As far as BacTalk, the latest software rev is Envision for BacTalk. It is not a replacement, just an upgrade and new name. Best thing about Alerton is they still support their legacy lines and BacTalk is backward compatible (to an extent) with their older product lines (not DOS-based, though). This can't be said of some other manufacturers' lines and reflects (IMO) a commitment to their customers with older, existing systems - meaning you don't have to completely replace your older systems to reap the benefits of more current and advanced features.