CB Antenna's and Radios?

What would you recommend for antenna's, which would work best the 5 foot fibreglass one or the K40 Steel antenna?  Looking for best reception and further distance.

Cobra or Uniden or any other preferred brand?

Basically the longer and taller the antenna the better.  So long as the top is under 13'6" of course.  Steel whip is likely cheaper than the fiberglass and isn't quite as noticeable to vandals walking near by with baseball bats.  But given the ranges and power levels of the legal CB radios you're likely not going to get out that far anyhow.

I personally prefer the Cobra 75WXST simply because all you need to mount in view is the microphone which also contains the speaker and channel selector.  The "box" portion can be mounted out of sight in a convenient location.  You can also mount an external speaker and very likely use an ear bud if you don't want others listening to foul language. 

What type of vehicle will this be mounted on?  Mobile home, pickup or ?

On a motor home generally a No Ground Plane type of antenna is required.. Beyond tht what the prior reply said, Longer is better.. Do be aware though that if you put a 9 foot whip on a 12 foot roof you will have a much shorter antenna in just a couple of bridges.

Brands.. Cobra and Johnson are the big  boys in the CB business but I'd not discount Midland.  and I don't know if Johnson still exists.

Years ago (more than I care to admit) I worked a Christmas for Radio Shack... At that time one of the electronics mags did a review of several brands, Including Cobra, Johnson and Radio Shack (Realistic back then)  I will summarize their findings.

Cobra and Johnson's top of the line were roughly equal, as were their #2, #3 and so on down to their bargain basement models.. Roughly the same performance and price, features were different is all (Radios with SSB capability always have some kind of delta tune, As I recall on one it was Receive only, on the other receive and transmit both tracked, and no I don't recall which)

Radio Shack's #1 radio was roughly equal to the big boys's #2 for features and performance.. #3 for price.. This too continued down the page.. That is to say Radio Shack' #N was roughly equal to Johnson or Cobra #N+1 for performance (Close enough to be called equal in fact) and to their N+2 for price.. all the way down to the last model which was still cheaper than the big boys.. Oh, by the way, I owned that model  (Six chan crystal controlled) good radio for what I wanted it for.

I still have a Realistic of that vintage in the motor home. it's on Chan 13 if you ever see me on the road.