Has anyone compared the EMT 139st phonostage to others ?

The 139st can be bypassed with the proper cable. 

The issue is, is it worth Euro 5k ? This includes an external PSU so that it can be used with other turntables outside EMT.

"The 139s are very sought after and fetch high prices, but sonically they do not compete with good modern tube designs. The EMT-133 / V-83 is the best, if the curve is modified to RIAA. A pair of mono 139As come second, then the 139st. Forget the 155s! The 153s and the Swiss Eymann are better, but still not worth the money. If you find a 927 or 930 with the tube EQ, then sell the EQ. If you find one with a 155 or 153, use the chassis to build your own phono preamp inside. I often used a simple Neumann design with modern parts and first-class Neumann MC transformers (which outperform all transformers I know of) or our own Phonogen design. With the EMT preamps, you can not even get close to how these tables perform."

Heiner Jakobi, "The EMT 927 and EMT 930 Turntables", in the now missing US magazine "Sound Practices", Volume 4, Issue 16, pages 17-22 (no date, may be in the second half of the 90s published).

Thanks @lbelchev , I have read that review already. The thing is, I have heard the EMT 938 and 950 with TSD-15 cartridge, EMT SUT and EMT 155st phonostage. One thing I can tell you, even the 155 phonostage, which is considered "basic" by EMT standards does a marvelous job of creating a very alive and dynamic presentation. It doesn't sound slow, veiled, low resolution or less dynamic in any manner compared to a good $5k phonostage. In fact it presents music with a lot of authority and grandeur. So I have some confidence that 139st can't be bad.   

From what has been said online, it's a very mixed bag.  Some owners love it and think it competes with some of the best out there and then the other side of the coin say it's not so good.   There are some opinions of the 139st in the big EMT 927 thread within this Audiogon analog forum.