Despite being relatively easy, I loved Lemmings 3D. I did find the camera somewhat annoying though - to tell the truth, I almost always used Virtual Lemming mode.
The one criticism I would have is that the difficulty really seems all over the place - the last few levels of Mayhem are very well placed, but aside from that, it can be quite random at times - for example, the second-to-last level of Fun is quite easily harder than most of the levels in Tricky, and one level towards the end of Tricky, "Chocolate Drop", is harder than anything in Taxing except for maybe "T Minus 5 And Counting" and/or "Death Slide".
The rest of this post may contain mild spoilers; I've spoiler tagged the worst one, but you might want to avoid the rest of this post altogether if you don't want even the slightest hints.Another thing worth noting is that it's extremely plagued by backroutes - including the final level having one of the most major backroutes in Lemmings history, although it's not immediately obvious just by looking - in fact you might think it wouldn't work if you don't try it. The Mayhem level "Tower of Lemlab" also has a very major - and in this case, quite obvious - backroute.
There are however some very great levels in there, especially towards the end of Mayhem - "Raiders of the Lost Lemming", "Hole in One, Two, Three!" and "Fun Fair" all come to mind here, and perhaps the best level of all, "Critical Path"*.
(I've used level names as I don't remember the positions exactly.)
* A spoilery note on that one:
It might strike some people as a level that's annoyingly strict on time. All I can say is - if you're running out of time, you're doing it wrong - the tight-for-time solution can work, but there's a better way to do it.
It does get annoying when some levels are overly based on guesswork, though (with teleporters or springs) - one VERY major example of this is the Taxing level "Motherboard", which once you know which teleporter to use, is ridiculously easy.