Advantages of 4 rotary valve contrabass tuba over 5 rotors

[pjv]

As is well known the implementation of the 5th valve on the 5xJ's wasn't one of the instruments succeses and indeed many had the 5th removed.
One might argue that this could very well be the case on many tubas that have played better without the 5th: the 5th valve design was flawed in some way.
Just a thought...

[LCTuba89]

I've played 4 and 5 valve tubas. The only time I ever needed the 5th valve was when I was playing my old Melton 2155R. It was the only way to play 3rd partial E and Eb in tune. With my latest horn the 6/4 BMB BBb, I opted for 4 valves simply because all the pitches were manageable without the need of a 5th valve(That and the fact that the 5th only effects the 4th valve combos.) It was additional weight, additional cost, and an added potential point of failure. I also like the sturdy feel of a fixed thumb ring.

[southtubist]

Given identical models of tuba, the 4 valve tuba is lighter. That means I can throw it farther

Very important when the conductor mouths off one too many times.

[bort]

How about: Advantages of a LH 5th valve over a RH 5th valve, besides slide pulling being easier with all RH.

[southtubist]

I don't know that. Some others who have posted on tubenet know that.
Conn(King) 52/54/56J tubas probably aren't the world's greatest tubas, but (when I was a practice room jock - perhaps a decade ago or more) I had absolutely no trouble playing "Fountains of Rome" on a run-of-the-mill 52J brought by a friend (Mudman - memberlist.php?mode=viewprofile&u=329 , here on TubeNet) into my (former) brick-and-mortar store. (I couldn't imagine playing that passage on any 4-valve tuba C tuba, unless it was sousaphone-like in its response, and offered amazing "false" tones.)

I played on a 52J for a while- using the smallest Helleberg type mouthpiece I could get my hands on. Strangely enough I got a big/loud sound out of it on recordings. It sure sounded tiny under the bell, and felt like a toy in my hands, but out front it projected like crazy and wouldn't get edgy. The 6/4 Miraphone and my Alex could barely compete despite being larger instruments. I liked that horn, but it wasn't my horn. Plus, I liked the edginess I could get on my Alex more.

[EMC]

What about the difference between 5 and 6 valve F tubas?