The main reason I got this pump is because it can take the water down to under 1/2 inch (which I believe is the biggest selling point over most others). I added a float switch to it and put it in a sump to get rid of water that builds under the house whenever we get over 1 inch of rain in a day. We've had such rain and I heard it cycling every couple minutes for 10 seconds or such, so it's doing what I needed. I probably didn't dig as deep as I should have for the sump, but keeping the water level minimal seems easier than replacing it all.
When I first got this, I tried it out filling a 5 gallon bucket and pumping into another. I ran it till I heard it losing prime and instantly pulled the plug. After lifting the pump out (with a bit of water draining out of the pump) I did have 1/4 inch of water left in the bucket, but that tells me it does take the level down very low compared to many pumps (that often have their intake at over 2 inches high). Some may say the reason to have the high intake area is to not have it clog as easily (sucking the dirt off the bottom), but I have pretty clean water in my system (and hope I can keep it that way, even if it means cleaning once a year). There is a loose rubber plug in the conical section of the pump where some air bubbles out of that as you first submerge it (and a "Do not remove" is cast in the pump near it). Seeing that made me wonder if that would let the pump lose prime as the water level dropped, but it didn't (it acts as a check valve letting air out, but not in). They do say in the manual "starting water level 2 5/8 inch min" then "Pumps down to level under 1/4 inch" which makes sense to me (they are insuring enough water for priming).
If you're wanting high flow, get plumbing for it over 1 inch versus using a garden hose with the connector provided. FYI a 5/8 inch hose is considered borderline too-small even for high pressure hydraulics at 15gpm (or 900gph) with 20+hp motors driving them, so expecting higher flows thru such a hose from a 1/2 hp pump like this is crazy. It took about 25 seconds to do my test emptying a 5 gallon bucket with short garden hose connected, so that's ~12gpm (720gph) rate and doesn't seem "super slow" to me for those conditions (although some have said they think it has poor performance regardless of such conditions).
The one thing I'm not impressed with is a 1 inch hole for the suction on the bottom. On 99% of pumps they have 1 size bigger suction hole versus outlet with it always being harder for pumps to draw in fluids than push it out, yet this has a bigger outlet (1 1/4 inch). Maybe they are trying to make it seem bigger by oversizing the outlet port to advertise bigger numbers, but if they really want 40 gpm or 2400gph to go thru it a 1 1/2 inch suction opening would be much better.
Some other warnings I'll pass along, since this comes with no float switches or such, you need to carefully watch it when nearing the bottom of the water and pull the plug instantly if the pump starts sucking air to avoid damage (even 30 seconds of dry run can be that bad). Also to give you some hints on performance for pumping out basements etc, they show on the box in a bar graph these numbers for this pump:
at 0 vertical lift you get 2400gph
at 5 foot lift 2000gph
at 10 foot lift 1400gph
at 15 foot lift 900gph
I didn't see that info in the ads, so I hope that helps you realize just as many cars are advertized as having "400 horse power engine" which is a peak performance number in ideal conditions (not a "continuous duty" number), so is the "2500 gph" on this.