Philips Hue White Ambiance Smart Bulb Twin Pack LED [B22 Bayonet Cap] - 1100 Lumens £32.64 @ Amazon

Around that. The non ambience (I.e. Yellow) are usually around this price or included in the deal packs.

Most likely, but the 1600 lumens are so much more.

It really depends on the use case. After living with smart bulbs and devices for some time, I have started swapping the "smart wifi" bulbs to Hue. The reason is purely because it seems to be more reliable when it comes to connectivity. I use these to do simple things like turn on the outside lights between dusk and dawn, which most of the smart wifi bulbs will achieve too. The smart wifi bulbs would be fine, then periodically disconnect - Not the end of the world and just purely annoying.

For me, the colour capabilities are never used, but being able to fine tune the colour temp and brightness is convenient. One thing to note is that not all Hue bulbs can change from soft / warm white and some cannot change to different colours.

For Hue, you may also need a Hue Bridge or an Alexa with zigbee, depending on your requirements. I have a hue bridge, it helps with my automation needs.

If I just wanted to change the colour periodically, the generic ones (like you have mentioned) would probably be fine.

Great, that's a much better deal. Currys list these at £59.99 being the ambience ones. Dare I ask, were they on a special deal or something?