Works great, well-constructed, with no visible flaws.

Update:

I'm downgrading from my previous 5-star 'I Love It' review to 1-star 'I hate it'.

I originally ordered this in May 2013 and was shipped a product by "Scientific Equipment of Houston" (4488 ratings, 99% positive). That funnel was great, nice high walls to hold plenty of liquid, and a flat, smooth bottom for the filter paper to seal against, and smooth, good-quality glaze.

Unfortunately in April 2016, after many successful uses, I broke it (my mistake, not a product flaw, I was interrupted during a hot-filtering procedure and neglected to reheat the funnel before adding hot liquid and the thermal shock cracked the funnel). So I came back to Amazon hoping to get the same item again. I was pleased to see I could just hit the 'buy it again' button without wasting time reading reviews again to find a decent product.

Alas, when the funnel arrived, while it was very well packed, the product itself is low quality. On checking the more closely the vendor has changed, it is now "Scientific Strategies" (448 ratings, 96% positive). My fault I suppose for not realizing that clicking 'buy it again' means 'Buy something similar to this again, possibly from a completely different vendor'. WTF Amazon? Changing companies and products on a listing is completely broken, how long was my 5-star review was attached to this POS product misleading other buyers? If I wanted to take a chance on random quality I'd buy from AliExpress.

Anyway, here's why this new funnel sucks.

The sidewalls are quite short, so the funnel must be refilled more often, a problem that is made even worse if you have a layer of media (sand, diatomite, etc) above the filter. Very tedious to use.

Worse, the bottom is slightly dished so that filter paper will not easily lay flat, so if you use filter paper it wrinkles up around the edges and forms channels around and under the edges of the filter. If you are filtering something water-based It is possible to use the funnel if you poke and stretch the filter paper enough to get it to mostly conform to the dish shape, but that is tedious and seems likely to compromise the filter. If you're filtering solvents that don't make the paper floppy this funnel is completely useless.

Don't bother with with this one, it's cheaper than the other options, but you'll just be trading a few dollars for wasted lab time.
Works great, well-constructed, with no visible flaws. Update:

I'm downgrading from my previous 5-star 'I Love It' review to 1-star 'I hate it'. I originally ordered this in May 2013 and was shipped a product by "Scientific Equipment of Houston" (4488 ratings, 99% positive). That funnel was great, nice high walls to hold plenty of liquid, and a flat, smooth bottom for the filter paper to seal against, and smooth, good-quality glaze. Unfortunately in April 2016, after many successful uses, I broke it (my mistake, not a product flaw, I was interrupted during a hot-filtering procedure and neglected to reheat the funnel before adding hot liquid and the thermal shock cracked the funnel). So I came back to Amazon hoping to get the same item again. I was pleased to see I could just hit the 'buy it again' button without wasting time reading reviews again to find a decent product. Alas, when the funnel arrived, while it was very well packed, the product itself is low quality. On checking the more closely the vendor has changed, it is now "Scientific Strategies" (448 ratings, 96% positive). My fault I suppose for not realizing that clicking 'buy it again' means 'Buy something similar to this again, possibly from a completely different vendor'. WTF Amazon? Changing companies and products on a listing is completely broken, how long was my 5-star review was attached to this POS product misleading other buyers? If I wanted to take a chance on random quality I'd buy from AliExpress. Anyway, here's why this new funnel sucks. The sidewalls are quite short, so the funnel must be refilled more often, a problem that is made even worse if you have a layer of media (sand, diatomite, etc) above the filter. Very tedious to use. Worse, the bottom is slightly dished so that filter paper will not easily lay flat, so if you use filter paper it wrinkles up around the edges and forms channels around and under the edges of the filter. If you are filtering something water-based It is possible to use the funnel if you poke and stretch the filter paper enough to get it to mostly conform to the dish shape, but that is tedious and seems likely to compromise the filter. If you're filtering solvents that don't make the paper floppy this funnel is completely useless. Don't bother with with this one, it's cheaper than the other options, but you'll just be trading a few dollars for wasted lab time.