The controls can be a little confusing, as you're not told you need to hold Sneak to get off the bike, and might try punching the bike. Lag doesn't help with this, as the server has to acknowledge your keypress. Jump will cause you to wheelie. There is also a feature where a long fall (approx >6 m) will cause you to "stack" the bike and fall off it.
The bike can't travel up a full metre of height difference at once, and it travels faster on paved surfaces. Thus, it encourages the building of sloped and paved roads, and corners that aren't too sharp, but not overbuilding on roads for the sake of roads at the same time. I find it creates a much nicer built environment than making roads for car mods.
The physics model is decent at best. Turning sharp corners can be difficult, so you need to slow. The bike's brakes are not very good, except for dismounting which apparently instantly stops it. Wheelie-ing will improve the turning radius which doesn't make much sense but is helpful for turning street corners. Also you can wheelie when stopped..
The bike is best used on a nearby server in your region or singleplayer. You can really suffer in multiplayer if there is a high ping to the server, e.g. Australia to Germany. Also if the server struggles to load the blocks fast enough - though it's a pretty poor server in that cae. In case of lag, it can actually work out slower than walking. This is basically a limitation of Minetest as it stands.
The artwork works fine within the limitations of usual Minetest, i.e. no knees. It is skinsdb compatible. The recolouring feature is nice. Some people may find the helmet a bit unnecessary, depending on their bike culture.
The bike can also be stolen easily. Put it back in your inventory when done riding! Maybe I'll make a bike lock mod one day...