Lots to choose from then, but what points do you need to think about before making your purchase? The main point for consideration should be the type of angling you intend to be doing, and also a crucial factor, the length of your sessions, as this will dictate how long you'll have them on for at a time.
To start off with, let's take a look at what types of footwear are best suited to which types of angling. If you're a stalking, roving or mobile type of angler, you will be better off looking at some of the low cut boots for the majority of your fishing. These will be comfortable for long periods spent walking, and being more like a trainer in design will be much better suited to climbing trees and scrambling down riverbanks. Most low cut boots are waterproof and breathable, but if it's likely you are going to be coming into contact with the water on a regular basis, a slightly higher cut might be more suitable – especially if you won't be doing much climbing.
A good design to look at in such circumstances would be a field boot. A field boot offers a rubberized lower part of the boot, so it's totally waterproof and easy to clean, whilst the upper wall is made of fabric to ensure comfy walking. One thing to look out for, though, is whether the lining is fixed, i.e. stitched in and part of the boot, or removable in that it can be taken out of the boot altogether. Whilst those with a removable liner are great for session fishing, or as a winter boot to keep your feet nice and warm, they aren't too good for trying to walk long distances as the liners – which are often very thick – tend to move around within the boot itself.
An ankle, low, trail or high boot will usually have a fully stitched in liner, so they give you the best of both worlds, good comfort with good traction. It's probably the case that in time you'll get a few different types of footwear to suit the season. My preference for summer is usually a skate type trainer which is quite well protected but allows me to climb trees and stalk comfortably. In the winter I'll tend to be night fishing so will go with a pair of field type fishing boots with a removable liner. In the day, I'll wear them all the time but when in the sleeping bag at night, I'll whip them off and take out the liners. This way I can get them on is a second if the rods go.
For choose the best ice fishing boots who wants the benefit of comfort, needs to be able to walk good distances, and who will also come into contact with the water quite a bit, you then have the extreme type boot which rides quite a way up the shin. They will be much the same design as the low or ankle boot but, basically, allows you to go into much deeper water without getting your feet wet. Obviously, they are quite big and cumbersome and take quite a bit of lacing up, so they wouldn't be suited to night fishing, but would be ideal for the roving angler in the winter.
It's worth bearing in mind that most angling manufacturers who now offer boots are only taking their lead from the hiking and trail boot industry, and as such, in many cases, you can get just as much bang for your buck – if not more - by purchasing a good hiking or trekking boot from any number of long established brands who have been designing very similar boots for much longer!
Whilst comfort and warmth are usually the main factors people consider, for the session angler, ease of use has to come into it as well. If you're divvied up on a session the boots are going to be on and off quite a bit, so in such circumstances you might wish to take a look at some of the moon boot styles, which offer good insulating comfort, but have no laces so are much easier to take on and off during the session and during the night.