In article <31B425C2.4E35@po.pacific.net.sg>, jennylim@po.pacific.net.sg
says...

>Hi everyone. I have a Nikon FM2 body and a Vivita 28-70 lens for a year
>now. Until now ,the FM2 is the best SLR I have had. I have nothing of
>that sort to say about the lens tough, the picture is no as sharp as my
>friend's Nikon's len I've borrowed.
>Recently, I have an urge to upgrade to a super ZOOM (28 - 200) which I
>can have one lens to cover all the ranges required. From my
>investigation, there are 3 brands in the market having these 28-200
>ranges, namely SIGMA, VIVITA series1 and TAMROM. I am confuse about
>which one to buy. Which lens will gives the better reproduction
>(sharpness and detail)of the picture and which lens will be easier to
>do focusing. I was wondering if there are someone out there who can help
>me in deciding .

I think you have answered your own question in the first four lines....;-)
You are beginning to have a taste for quality in images (and ease of use),
and no 28-200mm lens will provide that. Any old Nikkor (with a VERY few
exceptions) will run rings around the cheap zooms in both performance and
ease of use. Cheap, compact zooms save space and weight, but have no other
virtues - buy one, if that is more important to you than image quality and
focusing ease (and low-light ability, with non-zooms).
Hope This Helps