I've been running a couple SpyLink Dark Verizon models in some remote mountainous areas where you only get cell signal in certain sweet spots. I'm using the optional external antenna to get 2-3 bars signal strength. I've been fairly impressed with the triggering sensitivity and photo quality. Make sure you realize that the photos sent to your phone app are much lower resolution than the ones kept on the SD Card to save on data fees, they still work to identify animals but you wont see great detail until you go pull the card and copy the original images/videos.
I just pulled up the app to check and one has been out for 3 weeks, taken 284 pictures, normally reports 3 bars of signal strength and the lithium batteries I put in are still reporting at 100% charged right now.
I think a lot of satisfaction will come down to your signal strength (pick Verizon or ATT based on the best coverage in the area where you'll put the cameras) and respectively how quickly and reliably you need to receive the images. I generally get them within a few minutes of them being taken in my situation if set to immediately send, but I normally set it to only send every couple hours to preserve battery. Also, make sure you understand the model specific features if you want much control over types of triggering/video, frequency of sending photos, doing time lapse, etc as there are big differences as you step up in price.
I read pretty mixed reviews so wasn't sure when I bought them but so far I'm pleased.
I got mine from trailcampro.com and they have a 90 day return window and 2 year warranty so you dont even have to deal with the manufacturer, so pretty low risk, and they were helpful with questions before I ordered.