For the money they are fantastic bits of kit. The pro has 2 ball bearings I believe so its not a 'true' pin for the pruists, but they are real work horses and a delight to use.
I was so impressed with mine I bought a year and a half ago I bought a sheffield cheap on ebay too.
If you search the forums there was loads of previous posts that discuss your question, as long as they have been transferred over from the 'old' site.
As for the rachett, thats the only issue, its a small knob on the back of the pin, which is not the easiest to turn off and on whilst fishing, but is possible. You can not adjust the tension, its either on or off.
They are made from machined aluminium (one piece) and the price of these reels hjas been steadily rising over the past year or so as they become ever more popular as they are as well made as pins costing twice the price.
Have a look on ebay for a bargain. They come with a very good pouch to keep them in also.
Any more questions let me know and will do my best to assist.
To finish, I would rate them as one of the best bits of kit I've ever bought. (value for money and performance wise)