Uses much less volume to take a hydrometer reading than in a standard tube. Has to be held perfectly level to keep the hydrometer from touching the side however it's quite simple. I do also get a few drips from leakage but I have no complaints over a few drops. For me this product is a necessity and makes the process easier.
I mostly use it for taking samples, after the krausen has fallen, to get a feeling for whether fermentation is done. Sometimes it dribbles, but since I'm immediately transferring to a cup for taste testing and taking a refractometer reading, it works perfectly well.
I have two, one for sours and one for "clean" beers. It makes sampling much easier, but it does leak from the bottom quite a bit. Just hold it over your sanitizer bucket when taking a hydrometer reading and its fine.
I like the item, but it leaks a bit. This is a general rule for this type of item, not just this particular brand. I drop in the hydrometer with a spin, and gravity readings can be taken from one dip. Just be quick, and hold it over a catch basin of some sort, to collect any drips or spills.
This product works well and is designed fairly well. It does leak a tiny bit which is annoying but it gets the job done. I have never tried to drop the hydrometer into it but I take samples when needed. I am glad that I purchased this product.
In theory it is a good idea - in practice there are some issues
Yes, it works as a thief, but as has already been stated, it leaks quite a bit. I've also found it difficult to get a good reading from the hydrometer due to the hydrometer sticking to the sides of the sample taker. And you have to get that reading fast since it is constantly leaking away.
For the effort involved you're better off using a standard theif, filling your sample jar and going from there. Or using a refractometer.
I'm not totally turned off on the idea, just not this particular unit.
I agree with Dave, this works great as a thief, and in theory it does work for hydro readings, but you really have to have steady hands and patience, to get it perfectly plumb and level, so that the hydro rests directly in the center and doesn't touch the sides.
I picked this thief up to enjoy the convenience of simply dropping my hydrometer in after taking a sample. It works fine as a thief but it leaks a good bit and the hydrometer tends to stick to the sides, leading to an inaccurate reading. If you wanted to give the hydrometer a spin, enough probably leaked out that you can't reach in to do so. Instead, I just use the tube the hydrometer came in to empty the sample and test.