is an efs 18-200mm is a good walk about lens

[Rebel t3i]

as per title
have an efs 17-55 is usm f2.8 but I find that's a bit short some times
also have a 55-250mm f4 IS and a 17-85mm f4-5.6 IS usm but I find I am often changing lenses
was thinking of the efs 18-200 f3.5-5.6 for walk abouts or the ef 28-135 mm f3.5 is usm or shall i just manage with what I have
camera bodys are the 400d and 600d

 

[RKC]

as per title
have an efs 17-55 is usm f2.8 but I find that's a bit short some times
also have a 55-250mm f4 IS and a 17-85mm f4-5.6 IS usm but I find I am often changing lenses
was thinking of the efs 18-200 f3.5-5.6 for walk abouts or the ef 28-135 mm f3.5 is usm or shall i just manage with what I have
camera bodys are the 400d and 600d

Common problem with slr kit, you have 2 bodies I would consider taking both 17-55 and 55-200 on the other.

 

[Rebel t3i]

the problem with going walk about is I only tend to have one camera round my neck and the other lens in my pocket
I think I'd look daft with two cameras round my neck
i could lumber the sling shot bag round with me but that gets a bit heavy
hence why I was thinking of the 18-200, one camera one lens on walkabout

 

[lizzy23]

I have the 18 - 200 as a walkabout and like it

 

[lucky_13]

You seem to have lenses that cover nearly the same range! 17-55 55-250 17-85 what is the point of getting another lens that covers the same range again!? Unless you'r selling the other lenses,the 17-85 should be enough as a walkaround lens it's not that difficult to change a lens on the go with a slingshot bag if u need the extra reach of the 55-250. Sell the 17-85 and the 17-55 and get a 15-85 is usm f/3.5-5.6 perfect as a walkaround lens and you'll have the 55-250 too for the extra reach. Or there's the tamron 18-270 if you wanted all in one.
My choice would be to sell the rest and get the following

Canon 35 mm f/2 usm
Canon 15-85 is usm f/3.5-5.6
Canon 70-200 is usm f/2.8 is usm

They are very very sharp lenses.
Good luck...