Active vs. Passive Step-Up Devices

I would appreciate all thoughts regarding the relative strengths and weaknesses of active vs. passive step-up devices. My cartridge output is 0.25 mV.
You need a lot of gain for that output cartridge. If you already have a mm phono input than a passive device into it will produce less noise for the MC cartridge. The Quicksilver or EAR would be good choices - the EAR has a more versatile setting situation. An active device into the phono preamp input would tend to produce more noise. If you are just wanting to use another input as your phono input than you will need an active device or stand alone phono preamp - you will definitely have more options with this setup aned some are extremely quiet.
Ljgj, thanks for your response. I plan on having some step-up transformers installed inside of my preamp. I always like to be informed prior to making a decision.
They can both be good. When using a tube phono stage, there is a great demand for quiet tubes when there is very high gain. This can cause some expensive tube buying. If you use a good quality step up transformer, it puts less demand on the noise factor in the tubes, because you'll get 20 db more gain, before it hits the tube phono section. With less gain needed from the tube section, the noise problem is less critical. With solid state phono sections, noise is less of a problem, but I think tube phono sections sound better, when they are done right.
Wellfed...The Signet transformer that I once used was about the size of a beer can. Lot's of luck getting it inside a preamp!
I will be using Graham Engineering transformers and I have been told that they will fit. Jensen transformers and the Stevens & Billington TX-103 will fit as well, I'm told. My preamp chassis is about 6" high.