How much difference will a phono stage upgrade make?


For the past couple of years I’ve slowly been upgrading my audio equipment. I currently have a Primaluna Dialogue Premium HP integrated amplifier, an EAT C-Sharp TT with an Ortofon Quintet Black MC cartridge, and Tannoy Revolution XT 8F speakers. The weak link at this point, it would seem, is my phono stage, which is a Pro-Ject Tube Box DS. All things considered, my system sounds really good to my ears, but I can’t help but wonder what a phono stage upgrade would bring to the table. I’m looking at the Manley Chinook Special Edition MK II, which is a big step up in terms of cost, but I wonder how much better it will actually sound. Has anybody made a similar upgrade, and was there a marked uptick in sound quality?
12hz
Thanks everyone for your useful comments. Ultimately I wasn’t looking for suggestions as to which phono stage to upgrade to, as I’ve done research ad nauseam and landed on the Manley Chinook Special Edition MK II. The Gold Note seems to have a lot of loyal fans, but I’m pretty firmly committed to the idea of tubes along my entire signal path. (Also, with the external power supply, the Gold Note ends up being substantially more expensive than the Manley.) That being said, the overwhelming enthusiasm expressed by everyone about the upgrades you all have made has me thinking that this would be a good move and money well-spent. Again, thanks for your comments. 
The Chinook will be a nice upgrade over the Tube Box and you should be very happy with it.
bpoletti:
Save your money and get a Herron Audio VTPH-2a. No need to upgrade when you have the best. The Herron is the last stop on the upgrade path.

Back when I was researching phono stages I came across a lot of comments just like this. Also more than a few deriding or mocking for being so up front about it. Now that I have one though I have to say, its basically true.

In fact only reason I can think of to qualify it with "basically" is there are people like the OP who have preferences for things other than pure sonic upgrades. The OP has his mind set on all tubes. Others have their mind set on features. Or whatever.

For those with their mind set on music, and especially for those musically minded listeners willing to listen and decide for themselves (hardly any reviews, Herron doesn't hand them out, you have to BUY one!) there may well be no better choice.
Every move in the phono stage link has made a big difference, positive and/negative. 
I’m currently using a Musical Surroundings Phonomena ii which I like a lot and is VERY flexible for just about any cart you throw at it.  There’s a ii+ out now.  
millercarbon:
The OP has his mind set on all tubes. Others have their mind set on features. Or whatever.

For those with their mind set on music, and especially for those musically minded listeners willing to listen and decide for themselves
I'm actually very much interested in the music above all else. (Aren't we all?) I'm not a gearhead and I have no means of doing comparisons between high-end components, as I live in a small city with no access to the equipment discussed here. I drove 1000 miles to audition my amplifier and speakers and I'm glad I did, but it's not always possible. Hence, I rely on these forums for information, with the understanding that others' opinions may not always mesh with my listening preferences. I'm not stubbornly set on tubes for arbitrary reasons, it's just that my amp is a tube amp and I really love it. (For how it translates the music!) By logical extension I figured a tube phono stage would share the attributes that I like in my amp. Again, I wasn't looking for specific recommendations, I was really just looking for a nudge from this community, some assurance that a big investment in a new phono stage wouldn't simply produce nominal results by comparison to my current, less expensive phono stage. I don't want to be underwhelmed after spending $2500. 

I'm sure the Herron phono stage is great. It's also $1000 more than my already stretched budget will allow. (And as others on this thread have already suggested, even the Manley may be more than I need for my current set-up.)

Anyway, thanks for your input. I hope that asking the question I asked didn't somehow imply that I care more about an allegiance to tubes than to the music. That's not at all the case. I'm trying to build a good system that I can eventually just forget about and enjoy my albums.