I have been installing Magnaclean filters for a few years now - a magnetic inline filter used to clean the c**p from heating systems and protect newly installed boilers from dirty old systems:
http://www.adeysolutions.co.uk.
Always game to try something new, Last week I purchased a new filter made by Fernox - The TF1:
http://www.fernox.com/?cccpage=Total_Filter_TF1&sub=11
My findings:
Installation:
Relatively easy to install. Found the valves awkward to get at to service the unit. Prefer Magnaclean setup.
Fernox claim more dirt capacity and easier servicing than Magnaclean. The system last week was a good test because it was really dirty. I removed the lid after an hour and the filter was full - any more and it would have blocked the flow. It had trapped quite a bit of sludge, but Magnaclean definitely holds more dirt, no question.
Servicing:
This is where it went pear shaped. Fernox say you can just remove the magnet from its tube and open the bottom drain valve and flush through. So with the sludge still attached I replaced the lid assembly (this is a pain as you have to line up 4 'lugs' with matching cavities and I found it hard to keep the o'ring seal in position) and flushed the unit as per instructions.
There are two glaring problems with TF1:
a. the black water sprayed everywhere! Spent a few minutes cleaning up.
b. When I checked the magnet tube assembly again, I was amazed to find at least half of the dirt still inside the canister - after flushing it!! It was fortunate that I checked - I bet most plumbers won't bother - and it would have meant that for the next year until I return to service it, the filter would have only had half the capacity left to fill. This is a stupid design, or should I say stupid servicing technique, and made me a bit mad actually. When you clean a Magnaclean, a simple process, you can see it is 100% clean. When you clean it you always clean it fully. It's just a better design than TF1.
I contacted Adey who make the Magnaclean filter and spoke to their technical team. They said they are fully aware of the design issues with Fernox total filter 1 (TF1), and that they had made a see-through version of TF1 and found that TF1's ability to catch non-magnetic debris is almost non-existent. They said the dirt 'vortex's' back out of the filter and into the system again. They would say that I suppose, but as a fairly technical chap myself, you can see that they are probably correct just by looking at the funnel shape design. TF1 is not a Dyson!
So this is my 'opinion' of the TF1. My old dad always said you get what you pay for in life. Magnaclean may be a bit more expensive, but it seems the design is right, so I'm sticking with them

I would be interested to hear if any of you have tried a TF1. Check the magnet part after following Fernox instructions, I bet it is still dirty :-0
Have fun! I hope this helps.